Answer:
A. There are not 15 successes and 15 failures. A confidence interval can be computed by adding 2 successes and 2 failures.
Matt needs to travel 3 hours.
If 40km=1 hour
400km=? But there are two distances
200/40*1=5 hours
Therefore Kali needs to travel 5 hours to be 200 km away from the house.
If 50km=1 hour
200km=?
200/50*1hr=4hrs Therefore Matt needs to travel 4hrs to be 200 km away from the house. But Kali traveled 1hr earlier than Matt. 4hrs-1hr=3hrs
Therefore Matt has to travel for 3 hours to be 400km away from Kali.
Let F be the father's current age, and E be Evie's current age.
F = E + 36 this is the current relation between the ages
F + 3 = 5(E + 3) this the relationship in 3 year (hence the + 3)
Then solve by substituting one equation into another:
(E + 36) + 3 = 5(E + 3)
E + 39 = 5E + 15
24 = 4E
6 = E
Evie's current age is 6.