Explain why 7×11×13+13 and 7×6×5×4×3×2×1+5 are composite numbers?

Asked by lhadontsering58 | 28th Sep, 2020, 12:52: PM

Expert Answer:

A number is composite if it is divisible by a number other than 1 and itself.
 
In the number 7 x 11 x 13 + 13, 13 is common in both the terms. So, it can be written as (7 x 11 + 1) x 13
This number is divisible by 13. Thus, it is a composite number.
 
In the number 7 x 6 x 5 x 4 x 3 x 2 x 1 + 5
5 is common in both the terms. So, it can be written as (7 x 6 x 4 x 3 x 2 x 1 + 1) x 5
This number is divisible by 5. Thus, it is a composite number.

Answered by Yasmeen Khan | 29th Sep, 2020, 12:19: PM