Question

Find the unit's digit in the product (2467)163 x (341)72.

Answer 1

Clearly, unit's digit in the given product = unit's digit in 7¹⁵³ x 1⁷² 

Now, 74 gives unit digit 1. 

7¹⁵² gives unit digit 1, 

7¹⁵³ gives unit digit (1 x 7) = 7. 

Also, 1⁷² gives unit digit 1. 

Hence, unit's digit in the product = (7 x 1) = 7.