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Science, Technology, Engineering and Mathematics

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Math Antics | Math Video Lessons for Free plus more

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Math Antics | Math Video Lessons for Free plus more

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- [Voiceover] Compare 98,989 and 98,899. So we want to compare these two numbers and to do that, let's first think about what these digits mean. What do these numbers actually mean? Looking first at our number on the left, we have a 9 all the way to the right, or in the ones place value, which means just that. It means nine ones. Beside that, we have an 8 in the 10s place value, so that's eight 10s or 80. This number, these two right here, 89 is the same as an 80 plus a 9. Beside the 8, we have a 9 in the 100s place value, so again, we can look at that, 989 is the same as a 900 plus an 80 plus a 9 and let's keep going and fill in these last two. We have an 8 in the 1,000s place, and finally, a 9 in the 10,000s place, which means nine 10,000s or 90,000, so 98,989 is the same as 90,000 plus 8,000 plus 900 plus 80 plus 9. Which of these place values now seems like the most important one if we're deciding how big a number is? Which one of these has the biggest impact on the size of our number? And the answer is the one all the way to the left, whatever place value is farthest to the left is the greatest place value, so it is the most important in deciding how big or how small a number is. So when we compare these numbers, we're going to start by comparing the largest place value that either of them has. In this case, 10,000s is the largest place value both of them has, and in both cases, it's a 9, so both of these numbers start with 90,000 which is equal, we can't tell yet which one is greater, so we're going to move to the next biggest place value. The next largest place value is the 1,000s and again, we can see in both cases, we have an 8 or 8,000, so looking at what we've compared so far, these numbers are identical, neither is larger than the other, so we're going to keep going and again, we're going to pick the next largest place value, which is the 100s and our first number on the left, we have nine 100s, nine 100s, but on the right, we have eight 100s, so eight 100s is less than nine 100s, so this number on the right is less than our first number, the number on the left, or we could say, the 900 is greater than 800 so the number on the left is greater and this is our greater than symbol because we want the open side to be facing the larger number. We want the open side facing the larger number. So we'd read this as 98,989 is greater than 98,899. And you might be thinking, but wait, we didn't look at the 10s and look at the 10s. Here, we have eight 10s, but on the right we have nine 10s. Well, nine 10s is definitely greater than eight 10s but it doesn't make up for having less 100s. 100s are far bigger, 10 times bigger, than 10s, so they matter more, they had a bigger impact on which of these numbers was larger. So, we compare until we find the greatest place value that's different and then whichever of those has the greater number in that place value is the greater number. Let's try one more. So here we're comparing 53,000 and 350,000. At a quick glance, you might be thinking, okay, first number 5, first number 3. The highest place value is bigger here, it's a 5. But that's not quite enough. We still have to be sure we're comparing the same place values. This largest place value here, this 5, is in the 10,000s place. But the largest place value over here, the 3, is in the 100,000s place. So we are actually comparing 300,000 to 50,000. Those are two different place values. We want to compare 100,000s to 100,000s, so looking over here, how many 100,000s did this number have? And the answer is a great, big zero. It has zero 100,000s, so we can say zero 100,000s and when we compare that to 300,000, that's far less. No 100,000s is much less than three 100,000s, so actually, this second number is larger, so be careful not just to compare the first number but the largest place value, and if there's no digit in that place value, we can fill in a zero and then compare. So to read this, we'll say 53,000 is less, less, than 350,000, and this symbol is less than because the larger side is open to the bigger number and the bigger number is the second number, so 53,000 is less than 350,000.

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Voiceover] Compare 98,989 and 98,899. So we want to compare these two numbers and to do that, let's first think about what these digits mean. What do these numbers actually mean? Looking first at our number on the left, we have a 9 all the way to the right, or in the ones place value, which means just that.

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Sharing in an app allows educators to pose problems and investigations for students by using an 8-character code or link. Students can share their thinking with their teachers and classmates. Share codes remain available for continued use for 18 months from the date they are last accessed.
Watch the video to learn how sharing works.

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Sharing in an app allows educators to pose problems and investigations for students by using an 8-character code or link. Students can share their thinking with their teachers and classmates. Share codes remain available for continued use for 18 months from the date they are last accessed.

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Rounding whole numbers to nearest hundred

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Sal rounds 24,259 to the nearest hundred.

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Soccer Math - Rounding provides a fun way for kids to practice rounding numbers. There are three different levels of difficulty: Tens & Hundreds, Tens, Hundreds & Thousands, and Tens, Hundreds, Thousands & Decimals. Get 5 correct in-a-row to take penalty shots!

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Sal solves a 2-step estimation word problem.

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Solve two-step word problems with addition, subtraction, multiplication, and division. Some questions include estimation.

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Math Antics | Basic Math Videos and Worksheets

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This website requires cookies to be enabled in order to work properly. But don't worry, we do not use third-party cookies or track your activity on other sites. Once you have cookies enabled, you can click here to go to the Math Antics home page. ⚠️

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Math Antics | Math Video Lessons for Free plus more

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Drag 'N' Drop Math is an online workshop in which students can easily complete multi-digit addition, subtraction (with regrouping), multiplication, and division problems, using big and small draggable numbers. The workshop is totally customizable and gives immediate feedback. This is one of the top ten most popular programs on mrnussbaum.com

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Drag 'N' Drop Math is an online workshop in which students can easily complete multi-digit addition, subtraction (with regrouping), multiplication, and division problems, using big and small draggable numbers. The workshop is totally customizable and gives immediate feedback. This is one of the top ten most popular programs on mrnussbaum.com

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Converting feet to inches (video) | Khan Academy

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Learn for free about math, art, computer programming, economics, physics, chemistry, biology, medicine, finance, history, and more. Khan Academy is a nonprofit with the mission of providing a free, world-class education for anyone, anywhere.

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Math Antics | Math Video Lessons for Free plus more

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How Does A Seed Become A Plant? | Backyard Science | SciShow Kids

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The following information is available to all staff and students needing access to the Everyday Math Online platform. All usernames and passwords are linked to districted issued Office 365 accounts.

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password:dawsonmott

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Learn how to calculate the area of a square and rectangle. Math lesson for kids

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Number Squares Generator Magic Square Number Trick Number Squares Game Square Number Math FSA Song Square to Square On YouTube Square Numbers 3rd Grade Square Numbers and Square Roots Within a Square Numbers Another Triangular Numbers First 20 Square Numbers What Are Square Numbers Khan Find Square Root of 4 Number Square Worksheet

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Convert Yards to Feet Video
Convert Yards to Feet Video

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How to convert hours to minutes and minutes to seconds | Khan Academy

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Solve multiplicative comparison word problems by using a multiplication sentence

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In this lesson you will learn how to solve multiplicative comparison word problems by using a multiplication sentence.

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What I want to do in this video is talk about the two main ways that triangles are categorized. The first way is based on whether or not the triangle has equal sides, or at least a few equal sides. Then the other way is based on the measure of the angles of the triangle. So the first categorization right here, and all of these are based on whether or not the triangle has equal sides, is scalene. And a scalene triangle is a triangle where none of the sides are equal. So for example, if I have a triangle like this, where this side has length 3, this side has length 4, and this side has length 5, then this is going to be a scalene triangle. None of the sides have an equal length. Now an isosceles triangle is a triangle where at least two of the sides have equal lengths. So for example, this would be an isosceles triangle. Maybe this has length 3, this has length 3, and this has length 2. Notice, this side and this side are equal. So it meets the constraint of at least two of the three sides are have the same length. Now an equilateral triangle, you might imagine, and you'd be right, is a triangle where all three sides have the same length. So for example, this would be an equilateral triangle. And let's say that this has side 2, 2, and 2. Or if I have a triangle like this where it's 3, 3, and 3. Any triangle where all three sides have the same length is going to be equilateral. Now you might say, well Sal, didn't you just say that an isosceles triangle is a triangle has at least two sides being equal. Wouldn't an equilateral triangle be a special case of an isosceles triangle? And I would say yes, you're absolutely right. An equilateral triangle has all three sides equal, so it meets the constraints for an isosceles. So by that definition, all equilateral triangles are also isosceles triangles. But not all isosceles triangles are equilateral. So for example, this one right over here, this isosceles triangle, clearly not equilateral. All three sides are not the same. Only two are. But both of these equilateral triangles meet the constraint that at least two of the sides are equal. Now down here, we're going to classify based on angles. An acute triangle is a triangle where all of the angles are less than 90 degrees. So for example, a triangle like this-- maybe this is 60, let me draw a little bit bigger so I can draw the angle measures. That's a little bit less. I want to make it a little bit more obvious. So let's say a triangle like this. If this angle is 60 degrees, maybe this one right over here is 59 degrees. And then this angle right over here is 61 degrees. Notice they all add up to 180 degrees. This would be an acute triangle. Notice all of the angles are less than 90 degrees. A right triangle is a triangle that has one angle that is exactly 90 degrees. So for example, this right over here would be a right triangle. Maybe this angle or this angle is one that's 90 degrees. And the normal way that this is specified, people wouldn't just do the traditional angle measure and write 90 degrees here. They would draw the angle like this. They would put a little, the edge of a box-looking thing. And that tells you that this angle right over here is 90 degrees. And because this triangle has a 90 degree angle, and it could only have one 90 degree angle, this is a right triangle. So that is equal to 90 degrees. Now you could imagine an obtuse triangle, based on the idea that an obtuse angle is larger than 90 degrees, an obtuse triangle is a triangle that has one angle that is larger than 90 degrees. So let's say that you have a triangle that looks like this. Maybe this is 120 degrees. And then let's see, let me make sure that this would make sense. Maybe this is 25 degrees. Or maybe that is 35 degrees. And this is 25 degrees. Notice, they still add up to 180, or at least they should. 25 plus 35 is 60, plus 120, is 180 degrees. But the important point here is that we have an angle that is a larger, that is greater, than 90 degrees. Now, you might be asking yourself, hey Sal, can a triangle be multiple of these things. Can it be a right scalene triangle? Absolutely, you could have a right scalene triangle. In this situation right over here, actually a 3, 4, 5 triangle, a triangle that has lengths of 3, 4, and 5 actually is a right triangle. And this right over here would be a 90 degree angle. You could have an equilateral acute triangle. In fact, all equilateral triangles, because all of the angles are exactly 60 degrees, all equilateral triangles are actually acute. So there's multiple combinations that you could have between these situations and these situations right over here.

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Classifying triangles (video) | Shapes | Khan Academy

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What I want to do in this video is talk about the two main ways that triangles are categorized. The first way is based on whether or not the triangle has equal sides, or at least a few equal sides. Then the other way is based on the measure of the angles of the triangle.

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Lines of Symmetry: Grade 4 Module 4 Lesson 12

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Practice finding patterns in numbers | 3rd grade | Khan Academy

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Sal uses number lines and fraction models to show equivalent fractions.

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Bill Nye The Science Guy on Light Bending & Bouncing (Full Clip)

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Learn how light travels in a straight line and reflects off things. Also, our eyes dont make their own light. Our science videos for kids make light fun!

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Using Base 10 Blocks to Represent Decimals

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Writing Tenths and Hundredths with Decimals.mp4

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non fiction maps and line plots grade 4 - Bing video

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Comparing decimals example 1 | Decimals | 4th grade | Khan Academy

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https://www.youtube.com/watch?v=l0JyMFDNyjM

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Converting Units of Time (Hours to Minutes)

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learn to play

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Decompose Liters into Milliliters! || EngageNY Grade 3 Module 2 Lesson 9

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Decomposing shapes to find area (add) | Math | 3rd grade | Khan Academy

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Multiplication word problem example 1 | Multiplication and division | Arithmetic | Khan Academy

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Decomposing Fractions

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In this lesson you will learn how to decompose a fraction by breaking up the fraction into a sum of fractions.

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Comparing fractions of different wholes 1

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Sal shades visual fraction models to compare fractions.

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Ben helps Jan and Kyle resolve an argument by adding fractions. Download for free on the App Store : https://apple.co/2V7gQ0J Download for free on the Play Store : https://bit.ly/2GQrqW9

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adding tenths and hundredths - Bing video

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Adding 2 Tenths and 15 Hundredths Fractions to Decimals to Hundredths How to Convert a Fraction into Decimal Hundredths A Change 3 25 to Hundredths Fraction into a Decimal How to Convert Fractions to Hundredths Change Fraction to the Hundredths Decimals Math Fractions Adding T Hundredths Worksheet Tenth Adding Worksheet 5.Nf.1

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Subtracting Fractions with Like Denominators

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Subtracting Fractions with Like Denominators

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We're asked to subtract and simplify the answer, and we have 8/18 minus 5/18. So subtracting fractions is very similar to adding fractions. If we have the same denominator, the denominator in the difference is going to be the same as the denominators in the two numbers that we're subtracting, so it's going to be 18. And our numerator is going to be the difference between the numerators. So in this case, it is 8 minus 5, and this will be equal to 3 over 18, which is the answer, but it's not completely simplified, because both 3 and 18 are divisible by 3. So let's divide them both by 3. So you divide 3 by 3, you divide 18 by 3, and you get 3 divided by 3 is 1. 18 divided by 3 is 6, so you get 1/6. And just to see this visually, let me draw 18 parts. Let me draw 18 parts here. So it might be a little bit of a messy drawing. I'll try the best I can. So let me draw six in this direction. So that is three right there. We have another three, so that's six parts. And then let me split this into three columns. So there we go. We have 18 parts. Now 8/18 is equal to one, two, three, four, five, six, seven, eight. That's 8/18. And now we want to subtract five of the eighteenths, so we subtract one, two, three, four, five. Now, what do we have left over? Well, we have three of the eighteenths left over, so you have that right there. You have three of the eighteenths left over. Now, if you turn three of the eighteenths into one piece, how many of those bigger pieces do you have? This is one of those big pieces. Now, where are the other ones? Well, this is another big piece right here. This is another big piece right here, another one, another one, and another one. If you had 18 pieces and you merged three of the pieces into one, then you actually end up with only six pieces. You end up with six pieces. Hopefully, you see that each row is one of the pieces now, and the blue is exactly one of the six, so 3/18 is the same as 1/6.

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Subtracting fractions with like denominators (video) | Khan Academy

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We're asked to subtract and simplify the answer, and we have 8/18 minus 5/18. So subtracting fractions is very similar to adding fractions. If we have the same denominator, the denominator in the difference is going to be the same as the denominators in the two numbers that we're subtracting, so it's going to be 18.

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Subtracting Mixed Numbers with Unlike Denominators Subtracting Mixed Numbers with Like Denominators Khan Academy Subtracting Mixed Numbers Subtracting Mixed Numbers with Renaming Adding Mixed Numbers Subtracting Fractions with Whole Numbers Subtracting Mixed Numbers with Whole Numbers Adding Fractions with Same Denominator

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Finding the Differences with Fractional Line Plots

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Finding the Differences with Fractional Line Plots

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[4.MD.4-2.0] Fractional Line Plots - Common Core Standard

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Finding missing side when given area | Math | 3rd grade | Khan Academy

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Common Core Division Strategies- 4th grade

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L06.08 Expressing and Interpreting Remainders 2