SOLUTION: Justin has already saved $100 and wants to buy a playstation 2 for $129 about four weeks from now. To find how much he should save each week between now and then, he wrote 100+4x=1

Algebra ->  Expressions-with-variables -> SOLUTION: Justin has already saved $100 and wants to buy a playstation 2 for $129 about four weeks from now. To find how much he should save each week between now and then, he wrote 100+4x=1      Log On


   



Question 158951: Justin has already saved $100 and wants to buy a playstation 2 for $129 about four weeks from now. To find how much he should save each week between now and then, he wrote 100+4x=139.99. Explain this equation
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
I think you meant to write
100%2B4x=129
He's saving money to buy the PS2 for $129.
He starts out with $100.
The first week he saves, x, so his total is 100+x.
The second week he saves another x, so his total is (100+x)+x or 100+2x.
I think you see the pattern here.
Third week, (100+2x)+x or 100+3x.
After 4 weeks he will have 100+4x.
His goal is $129.
Set those two equal to each to find out what x should be.
100%2B4x=129
4x=29
x=29%2F4
x=$7.25
He needs to save $7.25 per week to buy the PS2.