SOLUTION: A box contains $7.70 in nickels, dimes, and quarters. There are 45 coins in all, and the sum of the numbers of nickels and dimes is 3 less than the number of quarters. How many coi

Algebra ->  Customizable Word Problem Solvers  -> Coins -> SOLUTION: A box contains $7.70 in nickels, dimes, and quarters. There are 45 coins in all, and the sum of the numbers of nickels and dimes is 3 less than the number of quarters. How many coi      Log On

Ad: Over 600 Algebra Word Problems at edhelper.com


    

Question 1173861: A box contains $7.70 in nickels, dimes, and quarters. There are 45 coins in all, and the sum of the numbers of nickels and dimes is 3 less than the number of quarters. How many coins of each kind are there?
nickels
dimes
quarters
Answer by josgarithmetic(39616) About Me  (Show Source):
You can put this solution on YOUR website!
system%285n%2B10d%2B25q=770%2Cn%2Bd%2Bq=45%2Cn%2Bd=q-3%29


Look at the last two equations.
system%28%28n%2Bd%29%2Bq=45%2Cn%2Bd=q-3%29;

q-3%2Bq=45
2q=48
highlight%28q=24%29---------------the quarters

---
---

system%28n%2B2d%2B5%2A24=154%2Cn%2Bd=21%29

system%28n%2B2d=154-120%2Cn%2Bd=21%29

system%28n%2B2d=34%2Cn%2Bd=21%29
Eq-E2:
highlight%28d=13%29

and you can find n.