Find HCF ..
Q. HCF of 222, 642, 1062, Option : a. 6, b. 8, c. 4, d. 2
Soln,
222, 642, 1062 → all divisible by 2
→ 111, 321, 531
111, 321, 531→ all divisible by 3
→ 37, 107, 177
No more common.
So, HCF = 2 × 3 = 6
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Q. The HCF (Highest Common Factor) of 153, 351 and 378 is ? Q. 153, 351 āĻā§°ā§ 378 ā§° āĻŽāĻšāĻ¤ā§āĻ¤āĻŽ āĻ¸āĻŽāĻžāĻĒā§ąā§°ā§āĻ¤āĻ (HCF) āĻāĻŋāĻŽāĻžāĻ¨ ?
Solution | āĻ¸āĻŽāĻžāĻ§āĻžāĻ¨
Prime factorization (āĻŽā§āĻ˛āĻŋāĻ āĻā§āĻŖāĻ¨ā§āĻ¯āĻŧāĻ): 153 = 32 × 17, 351 = 33 × 13 , 378 = 2 × 33 × 7
The common prime factor is 32 (āĻ¸āĻāĻ˛ā§ āĻ¸āĻāĻā§āĻ¯āĻžāĻ¤ āĻĨāĻāĻž āĻ¸āĻžāĻ§āĻžā§°āĻŖ āĻŽā§āĻ˛āĻŋāĻ āĻā§āĻŖāĻ¨ā§āĻ¯āĻŧāĻ āĻšā§āĻā§ 32 )
HCF = 32 = 9
Trick | āĻā§ā§°āĻŋāĻ
Check divisibility by 9: 153 ÷ 9 = 17, 351 ÷ 9 = 39, 378 ÷ 9 = 42
All three numbers are divisible by 9, and no larger common factor divides all three. (āĻ¤āĻŋāĻ¨āĻŋāĻāĻāĻž āĻ¸āĻāĻā§āĻ¯āĻž ā§¯ā§°ā§ āĻŦāĻŋāĻāĻžāĻā§āĻ¯, āĻāĻŋāĻ¨ā§āĻ¤ā§ ā§¯āĻ¤āĻā§ āĻĄāĻžāĻā§° āĻā§āĻ¨ā§ āĻ¸āĻžāĻ§āĻžā§°āĻŖ āĻā§āĻŖāĻ¨ā§āĻ¯āĻŧāĻ āĻ¨āĻžāĻāĨ¤)
Ans: (C) 9
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