Hey there!
An integer is a number without any decimals or fractions following it, such as -17, 5, 1000, etc. A rational number is any number that can be made into a fraction of two integers.
First, let's select all of our numbers that are NOT integers, which means that they will have things after the decimal point or a fraction.
0,4,-2,2/3,-1.8,16,3.2,-5/4
Now, we need to make sure that they are all rational numbers. Most numbers ARE rational. You don't need to make it into a fraction, but as long as it is a terminating or repeating decimal you are fine. Let's see what we have.
2/3=0.66666... Repeating decimal Rational
-1.8 Terminating Decimal Rational
3.2 Terminating Decimal Rational
-5/4= =1.25 Terminating Decimal Rational
The only numbers that are irrational are ones like pi or √2 that have digits that go on forever in no particular order.
Your numbers are 2/3, -1.8, 3.2, and -5/4.
I hope this helps!
