The difference between 100 and 38.4 is exactly four times that of a number. Find the number. (solution of equations)

The difference between 100 and 38.4 is exactly four times that of a number. Find the number. (solution of equations)


Let this number be X
100-4X=38.4
4X=61.6
X=61.6/4
X=15.4
This number is 15.4