# Math Help - coin problem

1. ## coin problem

Your friend found $8.25 in pennies, nickels, dimes and quarters while walking home from school one week. When depositing, she noticed she had twice as many nickels as pennies, 1 fewer dime than nickels, and 1 more quarter than nickels. How many quarters did she have? Why is it 21?? 2. Originally Posted by dannyc Your friend found$8.25 in pennies, nickels, dimes and quarters while walking home from school one week. When depositing, she noticed she had twice as many nickels as pennies, 1 fewer dime than nickels, and 1 more quarter than nickels. How many quarters did she have?

Why is it 21??
p(.01) + n(.05) + d(.10) + q(.25) = 8.25

p + 5n + 10d + 25q = 825

p = n/2 , d = n-1 , q = n+1

(n/2) + 5n + 10(n-1) + 25(n+1) = 825

solve for n ... then determine the value of q = n+1