The End As We Know It

Number Theory Level 1

What is the last digit of

$123 \times 456 \times 789 ?$

1 2 3 4 6 7 8 9

2 solutions

. .
Apr 3, 2021

$3 \times 6 \times 9 = 18 \times 9 = \boxed { 162 }$ , so the last digit will be $\boxed { 2 }$ .

A Former Brilliant Member
Jan 10, 2017

The solution here is to multiply 3 by 6 by 9 and that is 162, so the unit's digit is $2$ .