Question 1072176
There is likely a far easier way to do this, but this way gets there.
the number of sides*the interior angle is a 4:1 ratio, (3/1)(4/3)
The sum of the interior angles for n1 is n1(180n1-360)/n1 divided by
 n2(180 n2-360)n2
this ratio is 4.
cross-multiply and remove the leading n1 and n2 by canceling with the denominator
4(180n1-360)=180n2-360
but n2=3n1
720n1-1440=540n1-360
180 n1=1080
n1=6, hexagon, with interior angles 120 degrees
n2=18, with interior angles 160 degrees, 4:3 ratio.