Question

what is th unit digit in the product (3547)^153 * (251)^72

Answer 1

Answer:

Step-by-step explanation:

(3547^153) * (251^72) =

((3547*251)^72) * ((3547^4)^15) *(3547)

~ (1^72)*(1^15)*(7) (mod 10) ~

~ (1*1*7)(mod10) ~ 7 (mod 10).

thus the unit digit is 7