Sarah went to an electronics store, purchased 3 CDs and 5 DVDs, and spent $137. Michelle went to the same store, bought 2 CDs and 7 DVDs, and spent $161. How much does each CD sell for at the store?

a) $13

b)$14

c)$18

d) $19

Question

Sarah went to an electronics store, purchased 3 CDs and 5 DVDs, and spent $137. Michelle went to the same store, bought 2 CDs and 7 DVDs, and spent $161. How much does each CD sell for at the store? 

a) $13 

 b)$14 

 c)$18 

d) $19

anonymous · Answer

(b)

anonymous · Answer

Let x = price of CD and y = price of DVD
Therefore 3x + 5y = 137  ............(1)   for Sarah
               2x + 7y = 167  ............(2)   for Michelle
then u got simultaneous  equations
Subtract (2) from (1) to get:  x - 2y = -24
solve for y: y = 0.5x + 12  ............(3)
Substitute (3) into either (1) or (2) and solve for x (price of CD)
It should give you $14