Question

The phones at Century Cellphones vary in price depending upon demand. The average phone has a built in camera and costs x dollars. Phones with both a camera and an MP3 player are 35 dollars less than twice the cost of the phones with just the camera. Phones without any features are 100 dollars less than the cost of the phone with just the camera. Purchasing all three would cost at least $525.
a) Determine the inequality that represents this situation.
b) How much does the phone with just the camera cost?

Answer 1

a. let us say that:

a = cost of phones with camera

b = cost of phones with camera and mp3

c = cost of phones without any features

 

b = 2 a – 35

c = a – 100

a + b + c = 525

 

b > a > c

 

b. We are given three equations with three unknowns. So we can solve the problem.

 

a + (2 a – 35) + (a – 100) = 525

a + 2 a – 35 + a – 100 = 525

4 a – 135 = 525

4 a = 660

a = $165