Question

What is sum of the all 5 digit number using 1, 2 , 3 , 7 , 9 without repeating any of them?

Answer 1

Answer:

Sn= n/2[2a+(n-1)d]

Sn= 5/2[2×1+(5-1)1]

Sn=0

Answer 2

• Odd numbers don't add up to give you an even number. It is possible only in case of factorial.

3!+1+3+13+7=30  

3!+3!+3!+3!+3!=30

11+1+3+15=30

3! + 15 + 9 = 30