Question

Find the unit digit of 124¹²⁸ × 126¹²⁴

Answer 1

In 124¹²⁸, the unit digit of base 124 is 4 and the power is 128  ...(even power)

Therefore, unit digit of 124¹²⁸ is 4

Also in 126¹²⁴, the unit digit of base 126 is 6 and the power is 124  ...(even power)

Therefore, unit digit of 126¹²⁴ is 6

Product of the unit digits = 6 × 6 = 36

∴ Unit digit of the 124¹²⁸ × 126¹²⁴ is 6.