Question

Xuan Yun has a total of 24 coins in her piggy bank. Some of them are twenty-cent coins and the others are fifty-cent coins. Thetotal savings is $6.90. How many twenty-cent and fifty-cent coins does she have?

Answer 1

number of 25 cent coins --- x
number of 50 cent coins ---- 24-x

25x + 50(24-x) = 690

solve for x and back-substitute