Question

An elevator starts at the 6th floor. It goes up 7 floors twice, and then it goes

Answer 1

The second

6+(7×2)-10 = 10
20-(5×3)+12 = 17

Answer 2

The first elevator starts at 6th floor, and it goes up 7 floor twice, so it's going to be 6+2 x 7=6+14=20

The second elevator starts at 20th, it goes down 5 floor 3 times, then goes up 12 floor, so it's going to be 20-3 x 5+12=20-15+12=5+12=17.

20>17 so it's the first elevator.