Question

easy method to find unit product of 4 three digit numbers

Answer 1

Example 1: Find the Unit digit of 287562581

SolutionStep 1: We know that the cyclicity of 7 is 4.
Step 2: Divide the power 562581 by 4.
By doing that, we get a remainder=1.
Step 3: 1st power in the power cycle of 7 is 7. 
Hence, the answer is 7.

Example 2: Find the Unit digit of 13445 * 54336

Solution: Cyclicity of 5 & 6 is 1. Since 5*6=30, the unit digit of given expression is 0.