Question

PLZ HELP ME !!!! Which expressions below equal a rational number ? Choose ALL that apply !

Answer 1

Answer:

The correct option is are 2, 3 and 4.

Step-by-step explanation:

Rational number: If a number can be defined in the form of p/q where, p and q are integers and q≠0, then it is known as rational numbers. For example: 0.2, 1/3 and 1 etc.

Irrational number: If a number can not be defined in the form of p/q where, p and q are integers and q≠0, then it is known as irrational numbers. For example: 0.222..., √2 and π etc.

$\pi\sqrt{36}=6\pi$

It is an irrational number because π is an irrational number.

$7\sqrt{5}-\sqrt{245}=7\sqrt{5}-7\sqrt{5}=0$

It is a rational number.

$\frac{4}{5}+\frac{3}{8}=\frac{32+15}{40}=\frac{47}{40}$

It is a rational number.

$(4\sqrt{7})(2\sqrt{7})=(4\times 2)(\sqrt{7\times 7})=8(7)=56$

It is a rational number.

$\sqrt{100}+\sqrt{5}=10+\sqrt{5}$

It is an irrational number because sum of a rational and an irrational number is always an irrational number.

Therefore the correct option is are 2, 3 and 4.

Answer 2

(From top to bottom) wrong, right, right, right, wrong. This is because a irrational*an irrational number is rational, but a rational*an irrational is an irrational number