Chain Rule - MCQ 1 - Banking Exams MCQ

Answer – c) 30 Explanation : Let ‘m’ men are originally employed m*18 = (m -12)*30 m = 30

Answer –b) 2 days Explanation : Total work = 60*50 + 70*24 Now days = D D*60 = 60*50 + 70*24
We get D = 78, so 2 more days

Answer – b) 60 Explanation : Horse*Days = Bags 20*40 = 40 and 10*D = 30 (20*40)/(10*D) = 40/30
We get D = 60 days

Answer – d) 2.(2/15) Explanation : 28*4*8 = 84*5*D
D = 2.2/15 days

Answer – c) 50 Explanation : 10*18*9 = 40 ……..(1)
L*9*6 = 40 ……..(2)
Divide both equations We get L = 60, so additional 50 men must be employed

Answer – c) 6.25 days Explanation : (12*10*8)/(16*D*12) = 4800/6000
D = 25/4 days = 6.25 days

Answer – e) 3400 Explanation : 6600*64*850 = 6600*14*850 + M*34*825
we get M = 10000 so new troops = 10000 – 6600 = 3400

Answer – b) 30 Explananion : 50 boys taken the meal means only 1/2 meal is remaining So, G/60 = 1/2, we get G =30

Answer – d) 5 Explanation : 2m + 6w = 1/10, m + 3w = 1/20 D is the days required We have to find 4m + 12w = 1/d, 4*(m +3w) = 1/d 4*1/20 = 1/d We get d = 5

Answer – c) 240 Explanation : 10*5 = 40…….(1)
30*10 = H…….(2)
Divide both equations to get H We get h = 240

A) 8
Explanation: Washing cars is a work, so M1*H1*W2 = M2*H2*W1
10*6*40 = 15*H2*20
Solve, H2 = 8 hrs

D) 60
Explanation: Building 1 house is 1, 2 houses is 2, so M1*D1*H1*W2 = M2*D2*H2*W1
5*60*8*(2) = 8*D2*10*(1)
Solve, D2 = 60

B) 8
Explanation: 2m + 4w = 5D, so 10m + 20w = 1D 3m + 8w = 3D, so 9m + 24w = 1D So, 10m + 20w = 9m + 24w Solve, 1m = 4w From 1st equation(2m + 4w = 5D), 2*4w + 4w = 5D, or 12 women can do in 5 days, so 1 women in 12*5 = 60 days.
Now 3m+3w = 3*4w + 3w = 15 w 1 women in 60 days, so 15 women in 60/15 = 4 days But we are required to find twice work, so 15 women 1 work in 4 days so twice work in 8 days

D) 4
Explanation: 2m + 6w = 10 D Or 2(1m + 3w) = 10D Or 1m + 3w = 20D So 5(1m + 3w) = 20/5 Or 5m + 15w = 4D

D) 1
Explanation: After 6 days, now food is left for 40 men for (15-6) = 9 days, now same food is eaten by (40-4) = 36 men, let it last for x days, so 40*9 = 36*x Solve, x = 10 The food which was to last for 9 days for 40 men, now will last for 10 days for 36 men, so extra 1 day.

D) 84
Explanation: 5 m or 7 w 5m + 3w Cross multiply and put in denominator Days = 40*5*7/ [5*3 +7*5] = 28 so for thrice work, days = 28*3

A) 50
Explanation: Remaining work = 1 – 2/7 = 5/7 After 18 days, 5 women left and 2 men joined so 4 women joined (1m = 2w), now number of women is 5+4 = 9, so 10*18*6*(5/7) = 9*D2*6*(2/7)
Solve, D2 = 50

B) 4
Explanation: First find the number of carpets weave in first 20 days, after which order of more carpets came. So, In 50 days, 20 carpets, so in 20 days 20*20/50 = 8 carpets So in remaining 30 days, (20-8) = 12 carpets can be weave working 8 hrs each day Now number of carpets is (12+6) = 18, let no of hours is x, so H1*W2 = H2*W1
8*18 = x*12 Solve, x = 12 hrs So more hrs = 12-8 = 4 hrs

C) 10
Explanation: M2 = (10+2) = 12 men, W2 = 4*(1/6) = 4/6 So 10*5*3*(4/6) = 12*D2*5*(1/6)
Solve, D2 = 10

B) 40
Explanation: 2 men or 4 women or 5 children = 38 D So 1m + 1w + 1c = 38*2*4*5/(2*4 + 4*5 + 5*2)