Tennis racket marked up 50% to $36.76

I asssume we want to find the original price
so marked up 50% means if original price=100, then marked up price=50+100=150%

so
36.76=150%
hack, since 150=3 times 50 and 2 times 50=100, divide 36.76 by 3 then mutiply by 2

36.76=150%
divide both sides by 3
12.25333333333=50%
multiply both sides by 2
24.5=100%
original price=$24.50

That’d be 9 years or something