Can the number `6^n`, n being a natural number, end with the digit 5? Give reason.

Can the number 6^(n) , n being a positive integer end with digit 0 ? Give reasons.

Consider the numbers 4^(n) , where n is a natural number. Check whether there is any value of n for which 4^(n) ends with the digit zero.

Consider the numbers of the form 4^n where n is a natural number. Check whether there is any value of n for which 4^n ends with zero?

If the mean of first n natural numbers is (5n)/(9) , then find n

The mean of first n natural numbers is . . . . .

Find sum of first n natural numbers.

Variance of first n natural number is …………

Statement 1 The difference between the sum of the first 100 even natural numbers and the sum of the first 100 odd natural numbers is 100. Statement 2 The difference between the sum opf the first n even natural numbers and sum of the first n odd natural numbers is n.

Find the sum of all three digit natural numbers divisible by 7

Let an denote the number of all n-digit positive integers formed by the digits 0, 1 or both such that no consecutive digits in them are 0. Let b_n = the number of such n-digit integers ending with digit 1 and c_n = the number of such n-digit integers ending with digit 0. The value of b_6 , is