Find the greatest number which when divides 261, 853, and 1221, leaves a remainder of 5 in each case.
Show answer & explanation
Correct answer: D
Explanation
The correct answer is option 4 i.e. 16.
Prime factorization method
Subtracting 5 from each number, we get
⇒ 261 - 5 = 256
⇒ 853 - 5 = 848
⇒ 1221 - 5 = 1216
Now, prime factorization of 256, 848 and 1216
⇒ 256 = 16 × 16
⇒ 848 = 16 × 53
⇒ 1216 = 16 × 2 × 19
Now, the required number (HCF of 256, 848, and 1216) = 16