Question

${53}^3-{46}^3-7^3$ is divisible by:

• A. 6 and 9
• B. 2 and 21
• C. 21 and 23
• D. both (b) and (c)

Answer 1

The correct option is D both (b) and (c)

Since we know that if (a + b + c) = 0, then
$a^3+b^3+c^3$ = 3abc
Therefore ${53}^3-{46}^3-7^3=3\times 53\times 46\times 7$