Answer:
The number of cases prior to the increase is 50.
Step-by-step explanation:
It is given that the number of measles cases increased by 13.6% and the number of cases after increase is 57.
We need to find the number of cases prior to the increase.
Let x be the number of cases prior to the increase.
x + 13.6% of x = 57
[tex]x+x\times \frac{13.6}{100}=57[/tex]
[tex]x+0.136x=57[/tex]
[tex]1.136x=57[/tex]
Divide both the sides by 1.136.
[tex]\frac{1.136x}{1.136}=\frac{57}{1.136}[/tex]
[tex]x=50.176[/tex]
[tex]x\approx 50[/tex]
Therefore the number of cases prior to the increase is 50.
