time and work mcq pdf Model Questions & Answers, Practice Test for ibps rrb so officer sclae 2 3 single exam 2024

Answer: (c)

Given 12 men≡15 women≡18 boys

∴ 1 Man≡1.5 boys, 1 woman = 6/5 boys.

Now, 5W + 6B = 12B.

Required answer is calculated as follows :

Total no. of boys reqd. = 18 × [(15/16) × (8/9)] = 15 boys

The number of boys already present = 12.

Hence, 3 boys more required.

But 3 boys = 2 men.

So, 2 men are required.

Answer: (b)

Their relative speeds

= (4.5 + 3.75) = 8.25 km/h

Distance = 726 metres = ${726}/{1000}$ = 0.726 km

Required time = ${0.726}/{8.25}$ × 60 = 5.28 min

Answer: (c)

Ratio of times taken by A and B = 100 : 130 = 10 : 13.

Suppose B takes x days to do the work.

Then, 10 : 13 : : 23 : x ⇒ x = $({23 × 13}/{20})⇒ x = {299}/{10}$

A's 1 day's work = $1/{23}$ B's 1 days work = ${10}/{299}$

(A + B)'s 1 day's work = $(1/{23} + {10}/{299}) = {23}/{299} =1/{13}$

∴ A and B together can complete the job in 13 days.

Alternate Method :-

A is 1.3 times efficient than B

A and B complete the work in $({23 × 1.3}/{1.3 + 1})$ = 13 days

Answer: (a)

Distance to be covered by the thief and by the owner is same.

Let after time 't', owner catches the thief.

∴ 40 × t = 50$(t - 1/2)$

⇒10t = 25⇒t = $5/2 hr = 2{1/2}$ hr

Answer: (a)

1 man's 1 day's work = $1/{108}$

12 men's 6 day's work = $(1/9 × 6) = 2/3$

Remaining work = $(1 - 2/3) = 1/3$

18 men's 1 day's work = $(1/{108} × 18) = 1/6$

$1/6$ work is done by them in 1 day..

∴ $1/3$ work is done by them in 6 × $1/3$ = 2days