Question

A jar of quarters and dimes contains $20.00. There are 110 coins in all. How many of each are there?

Answer 1

There are 50 dimes and 110-50 = 60 quarters in the collection.

Explanation:

Let D be the number of dimes.

Then the number of quarters is (110-D).

The "value equation" is

10D + 25*(110-D) = 2000.

Simplify and solve for D:

10D + 2750 - 25D = 2000,

-15D = 2000 - 2750,

-15D = -750,

D = %28-750%29%2F%28-15%29 = 50.