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Keith's Coffee Shop makes a blend that is a mixture of two types of coffee. Type A coffee costs Keith $5.75 per pound, and type B coffee costs $4.05 per pound. This month, Keith made 140 pounds of the blend, for a total cost of $658.80. How many pounds of type B coffee did he use?

User CTABUYO
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1 Answer

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Answer:the number of pounds of type B coffee that he used is 86

Explanation:

Let x represent the number of pounds of type A coffee that he used in the blend.

Let y represent the number of pounds of type B coffee that he used in the blend.

Keith made 140 pounds of the blend. This means that

x + y = 140

Type A coffee costs Keith $5.75 per pound, and type B coffee costs $4.05 per pound. The total cost of the blend is $658.80. This means that

5.75x + 4.05y = 658.80 - - - - - - - - - 1

Substituting x = 140 - y into equation 1, it becomes

5.75(140 - y) + 4.05y = 658.80

805 - 5.75y + 4.05y = 658.80

- 5.75y + 4.05y = 658.80 - 805

- 1.7y = - 146.2

y = - 146.2/- 1.7

y = 86

x = 140 - y = 140 - 86

x = 54

User GtotheB
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