Find the multiplicative inverse of the following
(i) -13    (ii) -13/19    (iii) 1/5    (iv) -5/8 × -3/7    (v) -1 × -2/5
(vi) -1

Solution:

The reciprocal of a given rational number is known as its multiplicative inverse. The product of a rational number and its multiplicative inverse is 1.

(i) The Multiplicative inverse of -13 is -1/13

∵ -13 × (-1/13) = 1

(ii) The Multiplicative inverse of -13/19 is -19/13

∵ -13/19 × (-19/13) = 1

(iii) The Multiplicative inverse of 1/5 is 5

∵ 1/5 × 5 = 1

(iv) The Multiplicative inverse of -5/8 × -3/7 is 56/15

∵ -5/8 × (-3/7) = 15/56 and 15/56 × 56/15 = 1

(v) The Multiplicative inverse of -1 × -2/5 is 5/2

∵ -1 × (-2/5) = 2/5 and 2/5 × 5/2 = 1

(vi) The Multiplicative inverse of -1 is -1

∵ -1 × (-1) = 1

☛ Check: NCERT Solutions for Class 8 Maths Chapter 1

Video Solution:

Find the multiplicative inverse of the following (i) -13 (ii) -13/19 (iii) 1/5 (iv) -5/8 × -3/7 (v) -1 × -2/5 (vi) -1

NCERT Solutions Class 8 Maths Chapter 1 Exercise 1.1 Question 4

Summary:

The multiplicative inverse of the following (i) -13, (ii) -13/19, (iii) 1/5, (iv) -5/8 × -3/7, (v) -1 × -2/5 ,(vi) -1 are -1/13, -19/13, 5, 56/15, 5/2, and -1

☛ Related Questions:

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