how many of each and total $ for each

Question

 An auto parts store sold 5 times as many batteries as brake pads. The difference in the sales was 240. How many of each were sold?  

 

                  and

                                                                                                                                                      

 Tires sell for $150 each and rims sell for $200. Three times as many tires were sold than rims. Total sales were $3,250. How many of each were sold? What were the total sales in dollars for each?

Answer 1

1. let x = number of brake pads, then 5x = number of batteries

our equation becomes 5x - x = 240; solving x = 60, and 5x = 300

 

2. let x = number of rims, the 3x = number of tires

our equation becomes 3x • $150 + x • $200 = $3250 

solving, x = 5

Proof: 3•$150•5 + 5•$200 = 2250 + 1000 = 3250