Find the number of prime factors in expression (35)⁶ × (38)⁴?

Question: Find the number of prime factors in expression (35)⁶ × (38)⁴?

Solution:
35 = 5 × 7
∴ 35⁶ = 5⁶ × 7⁶

38 = 2 × 19
∴ 38⁴ = 2⁴ × 19⁴

∴ Total number of prime factors in expression: 6 + 6 + 4 + 4 = 20