Question

Find the largest common factor of 720 & 600.
1. 2⁴ × 3² × 5¹
2. 2³ × 3¹ × 5¹
3. 2³ × 3¹ × 5²
4. 2⁴ × 3² × 5²

Answer 1

Correct Answer - Option 2 : 2³ × 3¹ × 5¹

Given:

Numbers are 720 & 600.

Concept used:

First, break the numbers into prime factors.

Pick the least common power of each prime number from both the numbers.

Explanation:

720 = 2⁴ × 3² × 5¹

600 = 2³ × 3¹ × 5²

Least power of '2' is 3.

Least power of '3' is 1.

Least power of '5' is 1.

⇒ HCF = 23 × 31 × 5¹

∴ The largest common factor of 720 & 600 is 23 × 31 × 5¹

 You have to find the largest common factor and LCM stands for Lowest common multiple. HCF stands for Highest/largest common factor.