Keiko's Coffee Shop makes a blend that is a mixture of two types of coffee. Type A coffee cost Keiko $4.15 per pound, and type B coffee costs $5.25 per pound. This month's blend used four times as many pounds of type B coffee as type A, for a total cost of $980.85. How many pounds of type A coffee were used?

39 pounds of type A coffee were used.

Step-by-step explanation:

Let,

x be the pounds of type A coffee used

y be the pounds of type B coffee used

According to given statement;

4.15x+5.25y=980.85      Eqn 1

y = 4x    Eqn 2

Putting y=4x in Eqn 1

4.15x+5.25(4x) = 980.85

4.15x+ 21x = 980.85

25.15x = 980.85

Dividing both sides by 25.15

Hence,

39 pounds of type A coffee were used.

maximum area = xy = (16)(32) = 512 ft2

to maximize the area of the garden, the side of the fence parallel to the side of the house should be 32 ft long, and the other two sides should both have length 16 ft.'

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