Question

how to multiply subtract add and divide in rational numbers

Answer 1

Let's take 2/3 as an example Adding two rational number For eg 2/3+1/3=1 Multiplying two rational number 2/3*1/3=2/9 Dividing two rational number 2/3/(1/3)=6/3 =2

Answer 2

When the rational number is something simple like 3, or 0.001, then just use mental arithmetic, or a calculator!

But what about when it is in p / q form.

To multiply two rational numbers multiply the tops and bottoms separately, like this:

a/b×c/d.
To divide two rational numbers, first flip the second number over (make it a reciprocal) and then do a multiply like above:

a/b/cd.