Question

The cost of one CD and one DVD is $22. A DVD is $4 more expensive than a CD. Work out the individual prices of 1 CD and 1 DVD.

Answer 1

ets Price of a DVD is fixed i.e. 15

and One CD price is 5 (Not fixed)

In First situation

2 DVDs and 1 CD cost = 35 as given

2 x 15 + 5 = 35

Lets one CD price is 7.5

In Second situation

2 x 15 + 2 x 7.5 = 45

Its mean CD price may be between 5 to 7.5

In asked scenario, Martin has 50

1 DVD and 3 CDs?

1 x 15 + 3 x 7.5 = 37.5

37.5 is lesser than 50

Explanation:

Answer 2

CD = $9

DVD = $13

Explanation:

CD+DVD = 22

DVD = CD+4

substitute for DVD

CD +(CD+4) = 22

2CD+4 = 22

2CD = 18

CD = 9

DVD = 13