Answer
21 dimes
Work Step by Step
Make an equation to model this situation. Let's say dimes are $d$ and nickels are $n$. She has 25 coins, which are a combination of dimes and nickels.
$d + n = 25$
Dimes are worth 10 cents, and nickels are worth 5 cents. Rhonda has a total of 2 dollars and 30 cents.
$0.1d + 0.05n = 2.30$
Find the solution using any method. Here, we will use elimination
$d + n = 25$
$-d -0.5n = -23$
_______________________
$0.5n = 2$
$n = 4$
There are 4 nickels, and because there are 25 coins, there must be 21 dimes.
