Eight goes into seventeen two times with one remaining, and since the denominator always stays the same,

would be your mixed fraction.
If you just want to know what is the least common multiple of 20 and 15, it is 60. Usually, this is written as
lcm(20,15) = 60
Sin x is possitive in two quadrants :
quadrant I and quadrant II
in quadrant I, cos x is positive
in quadrant II , cos x is negative
so i think the answer is : quadrant II
hope this helps