SOLUTION: A total of $3.45 constisting of dimes and quarters was collected from a soft drink vending machine. If there are 3 more dimes than quarters, find the numnber of dimes and quarters.

Algebra ->  Coordinate Systems and Linear Equations  -> Linear Equations and Systems Word Problems -> SOLUTION: A total of $3.45 constisting of dimes and quarters was collected from a soft drink vending machine. If there are 3 more dimes than quarters, find the numnber of dimes and quarters.      Log On


   

Question 149034: A total of $3.45 constisting of dimes and quarters was collected from a soft drink vending machine. If there are 3 more dimes than quarters, find the numnber of dimes and quarters.
Answer by mangopeeler07(462) About Me  (Show Source):
You can put this solution on YOUR website!
d=number of dimes
q=number of quarters
coefficient=value of the coin

10d+25q=345--------------------because the total value of both the coins is 345 cents
d=q+3--------------------------because there are 3 more dimes than quarters

Plug d into the first equation
10(q+3)+25q=345

Distribute
10q+30+25q=345

Combine like terms
35q+30=345

Subtract 30 from both sides
35q=315

Divide both sides by 35
q=9

Number of quarters=9

d=q+3
d=9+3
d=12

number of dimes=12

So,
number or quarters=9
number of dimes=12