Wow, great solution, hectictar!

1- 0.25

2-0.35

So, 0.35+0.25=.6, or 60%

I agree with Melody!

Thanks so much, CPhill! Very good, yay!

Thanks so much, CPhill!

I understood it much better now! Thanks so much, CPhill!

Thank you, CPhill! Looks delicious!

If we try 17n-1, we see that 17*1-1=16 -works

17*2-1=33 -works

17*3-1=50-works

Thus, (C) is our answer!

Lol, that's true!

We know that the sum of the angles in any quadrilateral, is 360 degrees, so \(x+5x+15+3x-25+4x-20=360, x=30, 5x+15=150+15=\boxed{165}\)