In right triangle ABC in the figure above, if sin A = 0.6, what is sin B?
A couple ways to go about understanding this one. I think the easiest way is just to recognize that 0.6 = 6/10, so you can assume that the side opposite angle A is 6, and the hypotenuse is 10. Of course, that’d make a convenient Pythagorean Triple: always be on the lookout for 3-4-5s and their bigger cousins 6-8-10s!
So if one leg is 6, and the hypotenuse is 10, then the other leg must be 8. Therefore, the sine of angle B is 8/10 = 0.8.