15:3

If you mean the ratio 15:3:

• Simplified form: 5:1 (divide both terms by gcd(15,3) = 3)
• As a single fraction: 15/3 = 5
• If it’s a mixture with total parts: first part = 15/(15+3) = 15/18 = 5/6 ≈ 83.33%; second part = 3/18 = 1/6 ≈ 16.67%

Method: gcd(15,3) = 3; divide both by 3.

Which interpretation did you want, or would you like more practice?