How many pounds of each did the customer buy

Question

Yolanda has a gourmet coffee shop with two different types of coffee .type A cost 5.90 per pound and type B cost 7.00 per pound. A customer wishes to purchase a mixture of these using two times more of type A than type B .if the total cost is 60 how many pounds  of each did the customer buy

Answer 1

5.9A + 7B = 60

2A = B

 

Now plug in and solve.

 

5.9A + 7(2A) = 60

5.9A + 14A =60

19.9A = 60

A = 3.01

 

B = 2(3.01) = 6.02

 

5.9(3.01) + 7(6.02) = 60

17.76 + 42.14 = 60

59.9 = 60

 

Depending on whether or not they can buy fractional pounds, this is about as close as you'll get.  Odds are the answer is (3,6) but it might also be closer to (3.01, 6.02).