CAT 1998 Question Paper Question 81

Question 81

What is the digit in the unit’s place of $$2^{51}$$?

Solution

The last digit of powers of 2 follow a pattern as given below.

The last digit of $$2^1$$ is 2
The last digit of $$2^2$$ is 4
The last digit of $$2^3$$ is 8
The last digit of $$2^4$$ is 6

The last digit of $$2^5$$ is 2
The last digit of $$2^6$$ is 4
The last digit of $$2^7$$ is 8
The last digit of $$2^8$$ is 6

Hence, the last digit of $$2^{51}$$ is 8


View Video Solution


Create a FREE account and get:

  • All Quant CAT Formulas and shortcuts PDF
  • 30+ CAT previous papers with solutions PDF
  • Top 500 CAT Solved Questions for Free

Comments
cracku

Boost your Prep!

Download App