SOLUTION: Tim has 450 dollars more than Rin. After Tim spends sixty dollars on school supplies, Tim has 7 times as much money as Rin. How much money does Rin have?
Question 1179070: Tim has 450 dollars more than Rin. After Tim spends sixty dollars on school supplies, Tim has 7 times as much money as Rin. How much money does Rin have?
1.00 x -1.00 y = 450.00
After spending $60 Tim has 7 times what Rin has
1.00 x -7.00 y = 60.00 .............2
Eliminate y
multiply (1)by -7.00
Multiply (2) by 1.00
-7.00 x 7.00 y = -3150.00
1.00 x -7.00 y = 60.00
Add the two equations
-6.00 x = -3090.00
/ -6.00
x = 515.00
plug value of x in (1)
1.00 x + -1.00 y = 450.00
515.00 + -1.00 y = 450.00
-1.00 y = -65.00
y = 65.00
Ans x = 515.00
y = 65.00
$ 515.00 money Tim has
$ 65.00 money Rin has
using two variables to complicate the solution when only one variable is needed
expressing whole numbers using 2 decimal places
using a very roundabout path to the solution when there are much easier ones....
let x = # dollars Rin has
then x+450 = # dollars Tim has
After Tim spends $60, the number of dollars he has is 7 times the number Rin has:
ANSWER:
Amount Rin has: x = $65
Amount Tim has: x+450 = 515