Probably 93 because 31*3 which is 93 ;)
3.65 is less than
First, you must change the mixed number into a decimal so you can compare the two numbers.
Then, you must compare the terms.
3.65 < 3.75
3.65 is less than
Perimeter is the sum of the sides which is 9n-12 and since all 3 sides are equal then the length of one side is (9n-12)/3= 3n-4