Question

Give one example each to show that rational number are closed under addition subtraction and multiplication are rational number closed under division give two examples in support of your answer

Answer 1

Rational nos r closed under addition:

1+2=3 which is a rational no.

Rational nos r closed under subtraction:

10-2=8 which is a rational no.

Rational nos r closed under multiplication:20×4=80which is a rational no.

Rational nos r closed under division:

20