Rational Number

CLASS - 7

Rational numbers

Today in this slide we are going to learn about the properties of rational numbers...

_

JANVI WAHI

What Are Rational Numbers ?

A number that can be represented as p/q are called rational numbers. Where q is not equal to zero.

Multiple Choice

Let 's check your understanding ...

Q1 What is not the value of q in rational numbers ?

• ZERO

• ONE

What is a negative rational number?

A rational number, whose numerator is a negative integer and denominator is a positive integer, is called a negative rational number. Similarly, if the numerator is positive integer and denominator is a negative integer; is also a negative rational number.

What is a positive rational number?

A rational number is said to be positive if its numerator and denominator are either both positive integers or both negative integers. In other words, a rational number is positive, if its numerator and denominator are of the same sign

Rational number in the standard form

A rational number is in the standard form if its denominator is a positive integer and there is no common factor between the numerator and denominator other than 1

Equivalent Rational Numbers By multiplying or dividing the numerator and denominator of a rational number by the same integer, we can obtain another rational number equivalent to the given rational number.

Numbers are said to be equivalent if they are proportionate to each other.

Addition of two Rational Numbers with different denominator

If we have to add two rational numbers with different denominators then we have to take the LCM of denominators and find their equivalent rational numbers with the LCM as the denominator, and then add them.

Multiple Select

Q2 Add 2/5 and 3/7

• 29/35

• 30/56

Additive Inverse

Like integers, the additive inverse of rational numbers is also the same

EX:- a+[-a]=0

  Subtraction

If we have to subtract two rational numbers then we have to add the additive inverse of the rational number that is being subtracted to the other rational number.

a - b = a + (-b)

Multiple Choice

Subtract 4/21 from 8/21

• 4/21

• 21/4

  Multiplication

Multiplication of a Rational Number with a Positive Integer.

To multiply a rational number with a positive integer we simply multiply the integer with the numerator and the denominator remains the same

Multiple Select

Multiply 3/7 and 5/11

• 15/77

• 12/77

Division

Reciprocal is the multiplier of the given rational number which gives the product of 1.

Reciprocal of a/b is b/a

Multiple Select

Divide 3/7 and 4/11

• 33/28

• 32/28

THANK U