This is an incomplete question, the correct question is given below.
Find the missing number of each unit rate
and 
Answer : The missing number of each unit rate of
and
are, 3 and 4 respectively.
Step-by-step explanation :
As we know that a unit rate is a rate in which 1 is present in denominator.
Or we can say that,
A unit rate is also called a single unit rate that means it will compare 1 unit of some quantity to a different units of a different quantity.
As we are given that that unit rates:
and 
Now we have to determine the missing number of each unit rates.
So, we can write the given expression as:

When are dividing 15 by 5, we get:

Thus, the missing number is, 3
And

When are dividing 24 by 6, we get:

Thus, the missing number is, 4