How do I simplify the fraction 18/24 to its lowest terms?

To reduce a fraction to lowest terms, divide the numerator and denominator by their highest common factor (HCF). For 18 and 24, list factors or break into primes: 18 = 2 × 3 × 3 and 24 = 2 × 2 × 2 × 3. The common factors are one 2 and one 3, so the HCF is 2 × 3 = 6. Now divide both parts by 6: 18 ÷ 6 = 3 and 24 ÷ 6 = 4. So 18/24 simplifies to 3/4. To be sure it is fully reduced, check that 3 and 4 share no common factor other than 1, which is true. If you don't spot the HCF straight away, you can divide step by step, but using the HCF gets you there in one move.