Question

A coin bank has 250 coins, dimes and quarters, worth $39.25. How many of each type of coin are there?

Answer 1

The bank has `95` quarters and `155` dimes.

Explanation:

If the bank has only quarters and dimes, and its total amount of coins is 250, then be `x` the amount of quarters it has, it will have `250-x` dimes.

A quarter is worth `0.25$`, a dime is worth `0.10$` and the `250` coins together are worth `39.25$`. Therefore, we have the following equation:

`0.25x+0.1(250-x)=39.25`
`rarr 0.25x+25-0.1x=39.25`
`rarr 0.25x-0.1x=39.25-25`
`rarr (0.25-0.1)x=14.25`
`rarr x=14.25/0.15=95`
`rarr 250-x=155`