which of the followng is a rational number

a.2 square root 3
b. 2 pie
c.3.14444
d.0.123456

how do you figure this out explanation

2 answers

a is not
b is not
c might well be (we will check)
d I doubt it
now check c
78611/25000 = 3.14444 so yes

check d
nope

I used http://ericlin2.tripod.com/mis/ration.html
for checking c and d
thank you