Question

The number of DVD's sold at Fry's Electronics in a month was 920 and the number of DVD's sold decreased by 12 per month. The number of Blu-ray discs sold at Fry's Electronics in the same month was 502 and the number of Blu-ray discs sold increased by 26 per month. Write a system of equations to model th situation. If this trend continues, in how many months will the number of DVD's sold each month equal the number of Blu-ray discs sold each month? How many each disc is sold in that month?

Answer 1

Answer:

a) 11 months

b) 788 discs

Step-by-step explanation:

Let us represent number of months = x

For DVD's

The number of DVD's sold at Fry's Electronics in a month was 920 and the number of DVD's sold decreased by 12 per month.

Hence:

920 - 12x

For Blu ray

The number of Blu-ray discs sold at Fry's Electronics in the same month was 502 and the number of Blu-ray discs sold increased by 26 per month.

502 + 26x

Write a system of equations to model th situation.

a).If this trend continues, in how many months will the number of DVD's sold each month equal the number of Blu-ray discs sold each month?

To solve this:

DVD's = Blu-ray

920 - 12x = 502 + 26x

Collect like terms

920 - 502 = 26x + 12x

418 = 38x

x = 418/38

x = 11 months

b) How many each disc is sold in that month?

For DVD's

920 - 12x

x = 11

Hence:

920 - 12 × 11

= 920 - 132

= 788 discs

For Blu ray

= 502 + 26x

x = 11

Hence:

= 502 + 26x

= 502 + 26 × 11

= 788 discs

Therefore, 788 discs were sold in each month