Percents that are added together are combining percents.
That would be zero.
Obtuse means more than 90 degrees. A triangle's angles add up to 180 degrees so can't have two obtuse angles.
3. 16 months
60x=947
x=15.78333… = 16 months
4. 46 months
400x=18,091
x=45.2275 = 46