Question

3. Explain why 7 x 11 x 13 + 13 is a composite number.
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Answer 1

Step-by-step explanation:

Given 7×11×13+13

=13×(7×11+1)=3×78

This number is multiple of two integers.Hence it has more than two factors.Hence it is a composite number.

similarly in

7×6×5×4×3 ×2×1+5

=5(7×6×4×3 ×2×1+1)=5×1009

This number is multiple of two integers.Hence it has more than two factors.Hence it is a composite number.