Calculating HPR

Can someone explain how to solve below equation for HPR (1+HPR) power 365/90 = 10%

(1+x)^4.0556 = 1.10 1/4.0556 = 0.2466 (1+x) = (1.10)^0.2466 (1+x) = 1.0238 x = 0.0238 --> 2.38% = HPR

Thanks… Missed adding 1 to right side.

or plug all the options in X