Without knowing the shape selection you have i cant really say anything. But with a square you wouldnt have any whole numbers, nor would a triangle give you whole number, than again no shape that i can think of would give whole numbers.
Answer:
2.5
Step-by-step explanation:
(I'm assuming you're doing this the same way I learned it, if not I'm sorry if it doesn't make sense)
=
Cross multiply
12x=30
Divide
x=2.5
This is just one way to do the problem. An easier way is to simplify the fractions.
=
You can either cross multiply or figure out that 2 is half of four and simply divide 5 by 2 which will also result in 2.5