Step-by-step explanation:
If it takes you 31 seconds to go up 3 floors then it would take you 62 second because half of 6 is 3 and the problem tells you how long it takes to go up 3 floors. So to get 6 floors just double 31 to 62. So it takes 62 second or 1 minute 2 seconds.
Answer:
62
62 because 1-6 is double of 1-3.
so 31 x 2
i-
- 15
5 * -3 = -15