ShmoopTube

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Time to get your Shmoop on.

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A store sells 8 oz. bottles of water for $0.95 and 16 oz. bottles for $1.25.

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Matilda bought 26 bottles of water and spent $27.70. How many 16 oz. bottles did she buy?

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Here are your possible answers...

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To solve this problem, we first need to set up an equation.

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We know Matilda bought some number of 8-ounce bottles….at $0.95

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and some number of 16-ounce bottles at $1.25 each.

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Since we know the TOTAL number of bottles that Matilda bought is 26,

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we only need to use one variable x to represent the number of 8 oz and 16 oz bottles.

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Let's label the number of 16 oz bottles as x...

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then we can label the number of 8 oz bottles as 26 minus x.

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We can also use the formula that cost per each bottle times number of bottles equals

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total cost for the bottle to write our equation...

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so we get 0.95(26 - x) for the total cost of 8 oz bottles

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PLUS 1.25x for the total cost of 16 oz bottles...

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EQUALS 27.70.

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Distributing the .95... we get that 24.70 minus .95x plus 1.25x equals 27.70.

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Adding like terms... negative .95x plus 1.25x gives us .3x...

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subtract 24.70 from 27.70...and we get 3.

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Divide .3 from both sides...and we get that x equals 10.

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She bought 10 16 oz bottles! Answer's B.

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