Subtract : 4 9 f r o m - 1 6

Rational numbers are numbers that can be represented in the form of p q , where q ≠ 0 . Given rational numbers are 4 9 f r o m - 1 6 . We have to subtract these rational numbers. ⇒ - 1 6 - 4 9 The denominators of the given rational numbers are 6 & 9 . L.C.M. of denominators 6 & 9 i s 18 . ⇒ - 1 6 - 4 9 ⇒ - 1 × 3 18 - 4 × 2 18 ⇒ - 3 18 - 8 18 ⇒ - 3 - 8 18 ⇒ - 11 18 Hence, the required answer is - 11 18 .

Subtract : - 4 15 f r o m 3 10

Rational numbers are numbers that can be represented in the form of p q , where q ≠ 0 . Given rational numbers are - 4 15 f r o m 3 10 . We have to subtract these rational numbers. ⇒ 3 10 - - 4 15 = 3 10 + 4 15 The denominators of the given rational numbers are 10 & 15 . L.C.M. of denominators 10 & 15 i s 30 . ⇒ 3 10 + 4 15 = 3 × 3 30 + 4 × 2 30 = 9 30 + 8 30 = 9 + 8 30 = 17 30 Hence, the required answer is 17 30 .

Subtract : 3 - 4 f r o m 4 5

Rational numbers are numbers that can be represented in the form of p q , where q ≠ 0 . Given rational numbers are 3 - 4 f r o m 4 5 . We have to subtract these rational numbers. ⇒ 4 5 - 3 - 4 = 4 5 + 3 4 The denominators of the given rational numbers are 4 & 5 . L.C.M. of denominators 4 & 5 i s 20 . ⇒ 4 5 + 3 4 ⇒ 4 × 4 20 + 3 × 5 20 ⇒ 16 20 + 15 20 ⇒ 16 + 15 20 ⇒ 31 20 = 1 11 20 Hence, the required answer is 1 11 20 .

The sum of two rational numbers is 5 18 . If one of the numbers is 1 8 , find the other.

Rational numbers are numbers that can be represented in the form of p q , where q ≠ 0 . Let the other number be x The sum of the two rational numbers : 1 8 + x = 5 18 ⇒ 1 8 + 8 x 8 = 5 18 ⇒ 8 x + 1 8 = 5 18 ⇒ 8 x = 5 × 8 18 - 1 ⇒ 8 x = 5 × 4 9 - 1 ⇒ 8 x = 20 - 9 9 = 11 9 ⇒ x = 11 72 Hence, this is the required answer.

What number be subtracted from 7 - 8 to get - 13 12 ?

Rational numbers are numbers that can be represented in the form of p q , where q ≠ 0 . Let the other number be x The subtraction of the two rational numbers : 7 - 8 - x = - 13 12 ⇒ - 7 8 - 8 x 8 = - 13 12 ⇒ 8 x + 7 8 = 13 12 ⇒ 8 x = 13 × 8 12 - 7 ⇒ 8 x = 13 × 2 3 - 7 ⇒ 8 x = 26 - 21 3 ⇒ x = 5 24 Hence, this is the required answer.

What should be subtracted from 3 4 + 1 3 + 2 5 to get 1 2 ?

Rational numbers are numbers that can be represented in the form of p q , where q ≠ 0 . Let the number be x ⇒ 3 4 + 1 3 + 2 5 - x = 1 2 ⇒ 3 × 15 60 + 1 × 20 60 + 2 × 12 60 - x = 1 2 ⇒ 45 60 + 20 60 + 24 60 - x = 1 2 ⇒ 89 60 - x = 1 2 ⇒ 89 - 60 x = 30 ⇒ 89 - 30 = 60 x ⇒ x = 59 60 Hence, this is the required answer.

E M B I B E

Composite Mathematics For Class VIII>Number System>Chapter 1 - Rational Numbers>EXERCISE 1 (B)

S K Gupta and Anubhuti Gangal Solutions for Exercise 2: EXERCISE 1 (B)

Author:S K Gupta & Anubhuti Gangal

S K Gupta Mathematics Solutions for Exercise - S K Gupta and Anubhuti Gangal Solutions for Exercise 2: EXERCISE 1 (B)

Attempt the free practice questions from Exercise 2: EXERCISE 1 (B) with hints and solutions to strengthen your understanding. Composite Mathematics For Class VIII solutions are prepared by Experienced Embibe Experts.