Question

Find the unit digit of the numeric expression: ${124}^{128}\times {126}^{124}$.

Answer 1

Units digit of ${124}^{128}$ is 6 since the units digit of the base is 4 and the exponent is an even number.
Units digit of ${126}^{124}$ is 6 since the units digit of the base is 6.

Product of these units digit = 4 $\times$ 6 = 24
Units digit of this product = 4
Units digits of ${124}^{128}\times {126}^{124}$ = 4