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Victoria has 112 dollars and spends 14 dollars each day.
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How long will it be until she has no money left?
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Victoria is starting with 112 dollars and she spends 14 dollars each day.
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This means that she loses or subtracts 14 dollars each day.
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So maybe you think that we should use subtraction.
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Something like this, 112 minus 14, that would be for day one.
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Then, we’ll have to subtract 14 from day two and day three.
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We were just keep subtracting over and over and over again until there was no money left, until we got to zero.
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There’s actually a better way for us to solve this.
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Instead of using repeated subtraction, let’s use division.
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Let’s take the 112 dollars Victoria has, divide that by the 14 dollars she spends every day; that will give us the number of times she can spend 14 dollars — the number of days she can spend 14 dollars.
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We start by asking the question, how many times does 14 go into 11?
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But 11 is smaller than 14.
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We can make zero groups of 14 out of 11.
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Then, we ask the question, how many times could 14 go into 112?
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How many groups of 14 can we make out of 112?
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We know that 14 times 10 equals 140, so 10 is too bigger number.
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We could try nine: 14 times nine.
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Let’s see if we can make nine groups of 14 out of 112.
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We’ll need to multiply 14 times nine.
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Four times nine is 36, nine times one is nine, plus three is 12.
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Bring down the 12.
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14 times nine is 126, But 126 is bigger than 112.
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So nine is too big a number.
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Back to the drawing board, if nine was too big, perhaps eight will be the right amount.
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So we multiply 14 times eight.
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Eight times four is 32.
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Write down your two, carry your three.
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Eight times one is eight plus three, nine, 10, 11.
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Look at that!
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14 times eight is 112.
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So we write 14 times eight in our division box, we subtract 112 from 112, we get a remainder of zero.
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But what does this eight mean?
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What’s this division told us?
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It’s saying that 112 can be put in groups of 14 eight times.
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This means that Victoria could spend 14 dollars eight times before she had no money left.
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And since she spends 14 dollars every day, she can only do this for eight days before she ran out of money.
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By dividing 14 into 112, we were able to determine how many days it would be until Victoria ran out of money.
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Victoria would ran out of money in eight days.