Question

Out of 275 coins, 120 are quarters. Of the remaining coins, 20% are nickels and the rest are dimes and pennies. There are 3 pennies for every dime. How many pennies are there?

Answer 1

Given 120/275 coins are quarters, we can set up equations to find the nickels, dimes, and pennies, where “d” represents dimes, and “p” represents pennies.

275 - 120 = 155, and 20% of 155 = number of nickels. So…

0.20 • 155 = 31

There are 31 nickels.

Now to set up equations for dimes and pennies, given there are 3 pennies for every dime. The pennies and dimes must add to 124 since 155 - 31 = 124:

p = 3d

d + p = 124

We can substitute our value in:

3d + d = 124

4d = 124

d = 31

Therefore, there are 31 dimes. 124 - 31 = 93, so there are 93 pennies.

Hence, there are 93 pennies, 31 dimes, 31 nickels, and 120 quarters.