Answer: Speed in miles per hour is 45 mph.
Step-by-step explanation:
Since we have given that
Distance covered = 15 miles
Time taken to cover the above mentioned distance = 20 minutes
We need to calculate the speed in miles per hour ,
As we know the formula for " Speed " i.e.

Now, we will put the value of distance and time in the above formula:

Hence, Speed in miles per hour is 45 mph.
You would write it as -4 1/2
Answer:

Step-by-step explanation:
we know that
The compound interest formula is equal to
where
A is the amount that she will repay
P is the amount borrowed
r is the rate of interest in decimal
t is Number of Time Periods
n is the number of times interest is compounded per year
in this problem we have
substitute in the formula above
Find out the interest

substitute the values

He should change how much he puts into his account each month to $50