SOLUTION: Mark has a total of 21 coins consisting of nickels and quarters. The total value of the coins is $2.45. How many of each type of coin does he have?

Algebra ->  Customizable Word Problem Solvers  -> Coins -> SOLUTION: Mark has a total of 21 coins consisting of nickels and quarters. The total value of the coins is $2.45. How many of each type of coin does he have?       Log On

Ad: Over 600 Algebra Word Problems at edhelper.com


    

Question 1145239: Mark has a total of 21 coins consisting of nickels and quarters. The total value of the coins is $2.45. How many of each type of coin does he have?

Found 2 solutions by josgarithmetic, greenestamps:
Answer by josgarithmetic(39620) About Me  (Show Source):
You can put this solution on YOUR website!
n nickels
q quarters

n%2Bq=21, accounting for coins

0.05n%2B0.25q=2.45, accounting for $dollars

0.05%2821-q%29%2B0.25q=2.45------------------simplify this and solve.

Answer by greenestamps(13200) About Me  (Show Source):
You can put this solution on YOUR website!


If all the coins were nickels, the value would be 21($.05) = $1.05.
The actual total value is $2.45, which is $1.40 more than $1.05.
Trading a quarter for a nickel keeps the total number of coins the same but increases the total by $.25-$.05 = $.20.
To make the correct total of $2.45, the number of nickels that need to be traded for quarters is $1.40/$0.20 = 7

ANSWER: 7 quarters; the rest (14) nickels

CHECK: 7($.25)+14($.05) = $1.75+$.70 = $2.45