Answer:
The answer is "21"
Step-by-step explanation:
mn + 3r
m = 5
n = 4
r = 1/3
Now just substitute the values given in the question into the equation
5(4) + 3(1/3)
Multiply 5 and 4 to get 20
20 + 3(1/3)
3(1/3) cancels out and becomes 1
20 + 1
Add 20 and 1
21
So "21" is your answer
