Algebra, word problem

Question

A photographer purchases 30 rolls of black and white film and 25 rolls of color film. If the cost of each roll of color film is twice the cost of each roll of black and white film, what percent of the total cost of film is the price of a roll of color film?

Answer 1

Hi Tatyana,

 

We have 30 rolls of B&W film

             25 rolls of color film

 

X = price of B&W film

2X = price of color film

 

30X + 25(2X) = total cost of film

 

     25(2X)

--------------- • 100% = cost of color film as a percent of total cost

30X + 25(2X)

 

50X

-----  • 100% = 5/8 • 100% = .625 • 100% = 62.5%

80X