What is the greatest integer among the following by which the number 55 + 75 is divisible?
What is the greatest integer among the following by which the number 55 + 75 is divisible? Correct Answer 12
Concept:
Formula used:
- an + bn = {a + b} × {an-1 - an-2b + an-1b2 – ⋯ – abn-2 + bn-1}
Calculation:
Using an + bn = {a + b} × {an-1 - an-2b + an-1b2 – ⋯ – abn-2 + bn-1}
55 + 75 = {5 + 7} × {54 – 53 × 7 + ⋯ +74}
= 12 × {54 – 53 × 7 + ⋯ +74}
Hence, 55 + 75 is divisible 12.
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Feb 20, 2025