Answer:
13
Step-by-step explanation:
It is a two digit number that is less than 16. That means it's either 10,11,12,13,14 or 15. 13 is the only number with a three in the ones place.
1 2/3 + 3 1/3 = 5/1
5 5/6 - 5/1 = 5/6
5/6 was left
28 ft per min = 0.512064 km per hour
