WEBVTT
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Word Problems: Taking From
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In this video, we will learn how to solve problems to find the number of objects that are left after objects are taken from a group.
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Here’s a box of 10 doughnuts.
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If we take a doughnut from the box, how many will be left?
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Nine.
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We could write this as a subtraction sentence.
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We had 10 doughnuts at the start.
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We’ve taken one doughnut from the box.
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And there are nine doughnuts left.
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If we take another doughnut from the box, then the number we’ve taken is two and the number left is eight.
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We had 10 doughnuts at the start.
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We’ve taken two from the box.
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There are eight left.
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If we take three doughnuts, then there are seven left.
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If we eat four doughnuts, there will be six left.
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If we eat five, we’ll have five doughnuts left.
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If we take six doughnuts, there are four left.
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If we take seven doughnuts, there are three left.
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If we take eight, we’re left with two.
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If we take nine, there will be one left.
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And if we eat all of the doughnuts, there will be none left over.
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Taking doughnuts from the box is the same as subtracting.
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When we take objects from a group, the number that we have left goes down.
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And if we take all the objects from a group, there’ll be none left.
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Let’s practice taking objects from a group and counting how many are left.
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A child had seven marbles in their pocket, but four fell out.
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How many marbles are left?
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This is a word problem.
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We know the child had seven marbles in their pocket to start with, and we know that four of these marbles fell out.
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We have to work out how many marbles are left.
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To work out how many marbles are left, we need to take away the four marbles that fell out of the pocket from the seven we had to start with.
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We could model this word problem using counters.
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We’ve got seven counters because the child had seven marbles in their pocket.
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We know that four marbles fell out.
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So we need to take four counters away from all seven.
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One, two, three, four.
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How many are left?
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Let’s count.
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One, two, three.
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If we take four from seven, we’re left with three.
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If a child has seven marbles in their pocket and four fall out, they will have three marbles left.
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Matthew had four apples.
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He ate two of them.
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How many are left?
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Let’s try and write our word problem as a number sentence.
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We know that Matthew had four apples at the start.
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We also know he ate two of them.
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To find out how many apples Matthew has left, we need to take the two that he ate from the four he had to start with.
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This is a subtraction word problem.
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When we take objects from a group, it’s the same as subtracting.
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What is four take away two?
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To find out, let’s take two counters away from our group of four counters.
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One, two.
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How many are left?
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There are two counters left.
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If we take two from four, then we get two.
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Four take away two is two.
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If Matthew has four apples and he eats two, he will have two apples left.
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There are four frogs in a lake, and then three frogs jump away.
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How many are left?
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In this problem, we begin with four frogs in a lake.
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Three of the frogs jump away.
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How many frogs are left?
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We started with four frogs, but three of them jumped away.
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So to find out how many frogs are left, we need to take away three frogs from our four frogs.
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Four take away three leaves us with one frog.
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If we take three from four, we get one.
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If there are four frogs in a lake and three frogs jump away, there will be one frog left.
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What have we learned in this video?
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We’ve learned how to find the number of objects left after objects are taken from a group.
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We’ve also learned that if we take objects from a group, the number that we have left gets smaller.