Question

For any natural number “n”,the number 7n

can end with digit :

a. 7 b. 3 c. 9 d. 0
​

Answer 1

Answer:

I guess a

Step-by-step explanation:

i am not sure ...........

Answer 2

Answer:

For any natural number “n”,the number 7n can end with digit:

d. 0

Explanation:

If 7n has to end with the digit 0 for any natural number n, then it has to be divisible by 10. ie. its prime factorisation should have the factors of both 2 and 5 [ since 10=2x5 ] But we know that 7=7x1 By the fundamental theorem of arithmetics, we also know that there exist no other factors for 7. Thus we conclude that 7n cannot end with the digit 0 for any natural number n.