Question

I need help on this plz help

Answer 1

They will have the same amount after 5 car washes
the savings will be $100

Answer 2

Answer:

5 carwashes, Josh: $ 100 savings, Sandra: $100 savings

Step-by-step explanation:

First we need to find each of their formulas.

Formula for Josh: 50+10c=s

Formula for Sandra:25+15c=s

We can set these two to be equal to each other in order to find how many carwashes it takes for them to have the same amount of money.

50+10c=25+15c

25+10c=15c

25=5c

c=5

after 5 car washes, they will have the same amount of money.

now that we know that, we can plug that into each equation to find each of their savings after the 5 carwashes.

Josh's savings:

50+10c=s

plug in the amount of carwashes,

50+10*5=s

50+50=s

s=100 dollars of savings for Josh

Sandra's savings:

25+15c=s

plug in the amount of carwashes,

25+15*5=s

25+75=s

s=100 dollars of savings for Sandra