Answer:
Step-by-step explanation:
Let the number of cleaners be x
Let the time taken be y
This relationship is inverse
x = k/y
If x = 3 and y = 4
3 = k/4
k = 3*4
k = 12
To get the time it will take 4 people, we will substitute k = 12 and x = 4 into the expression x = k/y
x = 12/4
x = 3
Hence it will take 4 people 3 hours at the same rate