(i) –(11/18) + (-3)/9 + 2/(-3) (ii) (-9)/4 + 13/3 + 25/6 (iii) -5 + 5/(-8) + (-5)/(-12) (iv) –(2/3) + 5/2 + 2 (v) 5 + (-3)/4 +…
Answers:
(i) -(11/18) + (-3)/9 + 2/(-3)
= (-11)/8 + (-3)/9 + (-2)/3
= (-11 × 1)/(18 × 1) + (-3 × 2)/(9 × 2) + (-2 × 6)/(3 × 6) (∵ L.C.M. of 3, 9 and 18 = 18)
= (-11)/18 + (-6)/18 + (-12)/18
= (-11 – 6 – 12)/18
= (-29)/18
(ii) (-9)/4 + 13/3 + 25/6
= (-9 × 6)/(4 × 6) + (13 × 8)/(3 × 8) + (25 × 4)/(6 × 4) (∵ L.C.M of 4, 3 and 6 = 24)
= (-54)/24 + 104/24 + 100/24
= (-54)/24 + 104/24 + 100/24
= (- 54 + 104 + 100)/24
= 150/24
= 25/6
(iii) (-5) + 5/(-8) + (-5/-12)
= (-5)/1 + (-5)/8 + 5/12
= (-5 × 24)/(1 × 24) + (-5 × 3)/(8 × 3) + (5 × 2)/(12 × 2) (∵ L.C.M of 1, 8 and 12 = 24)
= (-120)/24 + (-15)/24 + 10/24
= (- 120 – 15 + 10)/24
= (-125)/24
(iv) –(2/3) + 5/2 + 2
= -(2/3) + 5/2 + 2/1
= (-2 × 2)/(3 × 2) + (5 × 3)/(2 × 3) + (2 × 6)/(1 × 6) (∵ L.C.M. of 3, 2 and 1 = 6)
= (-4)/6 + 15/6 + 12/6
= (-4 + 15 + 12)/6 = 23/6
(v) 5 + (-3)/4 + (-5)/8
= 5/1 + (-3)/4 + (-5)/8
= (5 × 8)/(1 × 8) + (-3 × 2)/(4 × 2) + (-5 × 1)/(8 × 1) (∵ L.C.M of 1, 4 and 8 = 8)
= 40/8 + (-6)/8 + (-5)/8
= (40 – 6 – 5)/8
= (40 – 11)/8
= 29/8