Find the HCF of 84, 126, and 168.
Show answer & explanation
Correct answer: D
Explanation
The correct answer is option 4 i.e. 42.
Prime factorization of 84:
⇒ 84 = 22 × 3 × 7
Prime factorization of 126:
⇒ 126 = 2 × 32 × 7
Prime factorization of 168:
⇒ 168 = 23 × 3 × 7
The common prime factors of 84, 126, and 168 are 2, 3, and 7 of the common prime factors.
Highest Common Factor= 21 × 31 × 71 = 2 × 3 × 7 = 42
The Highest Common Factor of 84, 126, and 168 is 42.