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Dalia had 70 Egyptian pounds to spend at the market.
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She spent two-fifths of her money on meat and one-fifth of her money on vegetables.
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How much did she spend in total?
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Let’s begin by identifying the key information in this question.
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We’re told that the total amount of money that Dalia has to spend is 70 Egyptian pounds.
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We’re also told that the fractions of the money that she spends on meat and vegetables are two-fifths and one-fifth.
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We’re then asked to work out how much she spent in total.
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First, let’s work out the total fraction of her money that Dalia has spent.
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We need to add together two-fifths and one-fifth.
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As these fractions have a common denominator of five, then the denominator of the result will be five and we can add the numerators together.
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Two-fifths plus one-fifth is equal to three-fifths.
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To work out how much Dalia spent in total, we need to calculate three-fifths of 70.
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When we see the word “of” being used in a calculation involving fractions, it means that we can multiply.
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Three-fifths of 70 means three-fifths multiplied by 70.
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So the calculation that we need to perform is a fraction three-fifths multiplied by an integer 70.
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Perhaps, the most common way to approach this is to think of the integer 70 as a fraction: 70 over one.
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We can then remember that the rules for multiplying two fractions together tell us that we need to multiply the numerators and multiply the denominators.
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The result will be three multiplied by 70 over five multiplied by one.
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We can actually simplify this fraction before we perform the multiplications, as both five and 70 have a common factor of five.
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Five divided by five is one and 70 divided by five is 14.
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So we can cancel the two numbers down.
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We could also have performed this cross-cancellation at an earlier stage.
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The calculation is now three multiplied by 14 over one multiplied by one.
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Three multiplied by 14 is 42 and one multiplied by one is one.
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So we have the fraction 42 over one.
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As the denominator of this fraction is one, the whole fraction is just equivalent to 42.
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The amount of money that Dalia spent in total is 42 Egyptian pounds.