The mode of this set of data is 12
Since they are moving in opposite directions, this is the same as Amy staying still and Erica biking at 10 meters per second away from her.
To travel 1km = 1000m at 10 meters per second, you need 1000/10 = 100 seconds.
The answer is 4.
8/x +13 = y --------> y * 2 = 30
divide 2 on both sides so y = 15
8/x + 13 = 15
- 13 - 13
8/x = 2
x =4
