You can't mentally solve it but you can plug it into a scientific calculator.
Get to the website:
1.) Search up Desmos on Google
2.) Click on Scientific Calculator and follow the steps below to get your answer
How to get the answer to y = sin^-1(7/12)
1.) Click on func
2.) Click on sin^-1
3.) Click on main
4.) Click on a/b
5.) Type in 7 for the numerator and 12 for the denominator
6.) And you'll get your answer on the right side as 35.68533471
Shown in the image.
