Problem number 26 of the Rhind Papyrus says:

Find a quantity such that when it is added to StartFraction 1 Over 4 EndFraction of itself the result is a 15.



The modern day equation that models this problem is x plus StartFraction 1 over 4 EndFraction x equals 15..

What is the solution to the equation?

x = 10
x = 12
x = 15
x = 30