Question

Carlos and Michael are collecting baseball cards. Carlos has 85 and buys 10 more each week. Michael has 120 and receives 5 more from his uncle every week. When will Carlos and Michael have the same amount?

Answer 1

Michael and Carlos will have the same amount after 7 weeks

Explanation:

Assume the total number of baseball cards that Carlos and Michael need to have to be equal is y, and the amount of time in terms of weeks that it will take for this to be achieved is x.

The following expressions can be derived

For Carlos to achieve y, he will need 85 and an addition of 10 per week (x):

y=85+(10x)..........equation 1

For Michael to achieve y, he will need 120 and an addition of 5 per week (x):

y=120+(5x)..........equation 2

Equating equation 1 and 2 to solve for x

85+10x=120+5x

10x-5x=120-85

5x/5=35/5

x=7

Number of weeks it will take Michael and Carlos to have the same amount=x=7 weeks