How will you show that (17 × 11 × 2) + (17 × 11 × 5) is a composite number? Explain.

Numbers are of two types – composite and prime. Prime numbers can be divided by 1 and only itself, whereas composite numbers have factors other than 1 and itself.

It can be observed that

(17×11×2) + (17×11×5) = 17{(11×2) + (11×5)}

= 17×{11×{(2) + (5)}} = 17×11×7

The given expression has 17, 11and 7 as its factors.

∴ it is a composite factor.