Question

explain why 7*6*5*4*3*2*1+5*7 is composite no.​

Answer 1

$7 \times 6 \times 5 \times 4 \times 3 \times 2 + 5 \times 7 \\ 7(6 \times 5 \times 4 \times 3 \times 2 + 5) \\ 7(725) \\ 5075$

Now, the prime factorization of 5075 would give us product of prime numbers

Hence, this a composite number