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Benjamin wants to buy new rollerblades.
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The price of a pair of rollerblades is 78 dollars and the sales tax is seven percent.
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Determine the total cost of the rollerblades.
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Sales tax is an additional cost that you have to pay on top of the price of an item.
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The total cost of the rollerblades is equal to the price of the rollerblades plus the value of their sales tax.
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The price of the rollerblades is 78 dollars and the sales tax is seven percent of this — seven percent of 78 dollars.
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We need to work out how much the sales tax comes to.
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We’ll consider one method using a calculator and one method without using a calculator.
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First, the noncalculator method: one percent of 78 dollars is equal to 78 dollars divided by 100.
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It’s 0.78 dollars or 78 cents.
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To find the value of seven percent, we can multiply this by seven: 78 dollars over 100 multiplied by seven.
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We can evaluate this multiplication using a column method.
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78 multiplied by seven is equal to 546.
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So the calculation is equal to 546 over 100, which is five dollars and 46 cents.
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This remember is the noncalculator method for calculating the sales tax.
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Now, let’s consider a calculator method.
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When we see the word “of” in a question about percentages, it means multiply.
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Seven percent of 78 dollars is the same as asking for seven percent multiplied by 78 dollars.
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Percent means out of 100.
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So we can replace seven percent with seven over 100.
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Now, we can use a calculator to perform this calculation.
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Just as in our noncalculator method, it’s equal to five dollars and 46 cents.
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Therefore, the total cost of the rollerblades is equal to the price 78 dollars plus the sales tax five dollars and 46 cents.
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The total price is 83 dollars and 46 cents.