## 15 May 2016

### SBI Clerk Prelims 2016- Practice Aptitude Questions (Time & Work)

SBI Clerk Prelims 2016- Practice Aptitude Questions (Time & Work) Set-40:
Dear Readers, Important Practice Aptitude Questions with solution for Upcoming SBI Clerk Exam, candidates those who are preparing for those exams can use this practice questions.

1).Ram and Harsh together can complete a work in 10 days. Ram alone can complete the same work in 15 days. In how many days will Harsh alone complete the work?
a)    25 days
b)    5 days
c)    30 days
d)    Cannot be determined
e)    None of these

2).Suresh can complete a job in 15 hours. Ashutosh alone can complete the same job in 10 hours. If suresh works alone for 9 hours and then stops. In how many hours Ashutosh will complete the job alone?
a)    4
b)    5
c)    6
d)    12
e)    None of these

3).In how many days can the work be completed by A, B and C together?
I.        A and B together can complete work in 6 days
II.        B and C together can complete the work in 3(3 / 4) days
III.        A and C together can complete the work in 3(1 / 3) days
Which of the above statement(s) is / are necessary to answer the question?
a)    Only I
b)    Only II
c)    Only III
d)    Any one of the three
e)    Information in all the three statements is necessary to answer the question

4). Abha completes a work in 12 days. While Vibha take 15 days to do the same work. Find the ratio of efficiency of Abha : Vibha
a)    5 : 4
b)    3 : 4
c)    5 : 6
d)    4 : 3
e)    3 : 2

5).To complete a work, A takes 50% more time than B. If together they take 18 days to complete the work, how much time shall B take to do it alone?
a)    30 days
b)    35 days
c)    40 days
d)    45 days
e)    None of these

6). A, B and C can complete a work in 10, 12 and 15 days respectively. They started the work together. But A left the work before 5 days of its completion. B also left the work 2 days after A left. In how many days was the work completed?
a)    4 days
b)    5 days
c)    7 days
d)    8 days
e)    None of these

7).12 men can do a piece of work in 10 days. How many men would be required to do the same work in 8 days?
a)    14
b)    18
c)    16
d)    12
e)    None of these

8). Fifty six men can complete a piece of work in 24 days. In how many days can 42 men complete the same piece of work ?
a)    18 days
b)    32 days
c)    98 days
d)    48 days
e)    None of these

9). A work can be completed by 26 men in 17 days. To complete the work in 13 days, the number of additional men required is
a)    9
b)    8
c)    6
d)    18
e)    None of these

10). 18 men can build a wall, 4.5 metres high, 0.8 metre thick and 150 metres long in 25 days. In how many days will 30 men build a wall 6 metres high, 90 metres long and 0.40 metres thick ?
a)    4 days
b)    6 days
c)    12 days
d)    Cannot be determined
e)    None of these

1). c) 2). a) 3). e) 4). a)   5). a) 6). c) 7). e) 8). b) 9). b) 10). b)

Solution:
1). (Ram + Harsh)’s 1 day’s work = 1 / 10
Ram’s 1 day’s work = 1 / 15
Harsh’s 1 day’s work = (1 / 10) – (1 / 15) = (3 – 2) / 30 = 1 / 30
Hence, Harsh will complete the work in 30 days

2). Work done by Suresh in 1 hour = 1 / 15
Work done by Suresh in 9 hours = 9 / 15 = 3 / 5
Remaining Work = 1 – (3 / 5) = 2 / 5
1 / 10 work is done by Ashutosh in 1 hour
2 / 5 work will be done by Ashutosh in  10 × (2 / 5) = 4 hours

3). The question has three variables i.e., the rate of work done per day by each A, B and C. We need to have three equations to solve the problem. This is possible only by using all the three statements given.
Let the rate of work done per day by A, B and C be denoted by x, y and z respectively.
x + y = (1 / 6)
y + z = (4 / 15)
x + z (3 / 10)
Adding the above equations we get,
2(x + y + z) = (1 / 6) + (4 / 15) + (3 / 10)
Or 2(x + y + z) = (5 + 8 + 9) / 30
Or 2(x + y + z) = 22 / 30
(x + y + z) = 11 / 30

4). Abha’s 1 day’s work
= 1 / 12 and Vibha’s 1 day’s work = 1 / 15
Ratio of efficiency of Abha and Vibha = 1 / 12 : 1 / 15 = 5 : 4
Hence, Abha is more efficient than Vibha.
Or
Ratio of time  = Abha : Vibha
= 12 : 15 = 4 : 5
Ratio of efficiency = Abha : Vibha = 5 : 4

5). Let B alone can do the work in x days
A can do the work in 3x / 2 days
According to the question
(1 / x) + (2 / 3x) = 1 / 18
(3 + 2) / 3x = 1 / 18
5 / 3x = 1 / 18
3x = 18 × 5
x = (18 × 5) / 3 = 30 days

6). Let the work be completed in x days
According to the question,
[(x – 5) / 10] + [(x – 3) / 12] + (x / 15) = 1
(6x – 30 + 5x – 15 + 4x) / 60 = 1
15x – 45 = 60
15x = 105
x = (105 / 15) = 7
Hence, the work will be completed in 7 days

7). No. of man days required = 12 × 10 = 120
No. of men required to complete the work in 8 days = 120 / 8 = 15 men
Or, Simply 12 × 10 = n × 8
n = 15 men
Method 2:
Product constancy method – when no. of days is decreased by (1 / 5) [10 – (1 / 5)(10) = 8]
No. of men would increase by 1 / (5 – 1) = 1 / 4
No. of men required = 12 + (1 / 4) (12) = 15 men

8). 56 × 24 = 42 × Number of days
Number of days = (56 × 24) / 42 = 32 days

9). 26 × 17 = no. of men × 13
No. of men = (26 × 17) / 13 = 34
Hence additional men required = 34 – 26 = 8