suppose you have 43 coins, all dimes and pennies that totals $2.68. How many of each coins do you have?

number of dimes ---- x

numbe of pennies ---- 43-x

10x + 1(43-x) = 268
9x = 225
x = 25

so she had 25 dimes and 18 pennies.

check: 10(25) + 18 = 268