Time and work questions

YOU CAN DOWNLOAD 200+ SUBJECTS PDF BOOK FOR COMPETITIVE EXAMINATIONS

CLICK HERE TO DOWNLOAD

Time And Work

Question 36 [CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
A single reservoir supplies the petrol to the whole city, while the reservoir is fed by a single pipeline filling the reservoir with the stream of uniform volume. When the reservoir is full and if 40, 000 litres of petrol is used daily, the supply fails in 90 days. If 32, 000 litres of petrol used daily, it fails in 60 days. How much petrol can be used daily without the supply ever failing?
A
60000 litres
B
56000 litres
C
78000 litres
D
64000 litres
Question 36 Explanation: 
Let X litres be the per day filling and L litres be the capacity of the reservoir, then

90X + L = 40000 * 90 ----------- (1)

60X + L = 32000 * 60 ----------- (2)

Solving the equation,

X = 56000 litres

Thus, 56000 litres per day can be used without the failure of supply.

Question 37 [CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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?
A
40 days
B
35 days
C
45 days
D
30 days
Question 37 Explanation: 
We have,

B = 3/2 *A

→ A = 2/3 *B

One day's work, (A+B) = 1/18

(2/3 * B + B) = 1/18

5/3 *B = 1/18

One day's work of B = 3/90

B alone can complete the work in,

= 90/3

= 30 days.

Question 38 [CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
A tank can be filled with water by two pipes A and B together in 36 minutes. If the pipe B was stopped after 30 minutes, the tank is filled in 40 minutes. The pipe B can alone fill the tank in:
A
90 minutes
B
75 minutes
C
60 minutes
D
45 minutes
Question 38 Explanation: 
Let the pipes fill the tank in x minutes.

Part of tank filled by pipes A and B in one minute: 1/36;

Part of the tank filled by pipe A in 1 minute = 1/36 - 1/x;

According to the question,

30* 1/x + (1/36 - 1/x) = 1;

→ 30/x + 10/9 - 40/x = 1;

→ 10/x = 1/9;

Hence, x = 90 minutes.

Alternatively,

% of tank filled by (A+B) in 1 minute = 100/36 = 2.78%;

% of tank filled in 30 minutes = 2.78 * 30 = 83%

That means 17% of tank can be filled by A in last 10 minutes;

Then, % tank filled by A in 1 minute = 17/10 = 1.7%;

% of tank filled by B in 1 minute = 2.78 - 1.7 = 1.1%

So, B alone can fill 100% tank in,

= 100/1.1 = 90 minutes (approx.)

Question 39 [CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
Two forest officials in their respective division were involved in the harvesting of tendu leave. One division had an average output of 21 tons from a hectares and other division, which had 12 hectares of land less, dedicated to tendu leaves, got 25 tons of tendu from a hectare. As a result, the second division harvested 300 tons of tendu leaves more than the first. How many tons of tendu leaves did the first division harvest.
A
3450
B
3600
C
3150
D
3500
Question 39 Explanation: 

Let First division have x hectare of the land then second division will have (x - 12) hectare of land.

Now according to the question,

25 *(x - 12) = 21x + 300

or, x = 150 hectare.

Hence, the first division harvest 3150 tons tendu leaves.

Question 40 [CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
A group of workers was put on a job. From second day onwards, one worker was withdrawn each day. The job was finished when the last worker was withdrawn. Had no worker been withdrawn at any stage, the group would have finished the job in 55% of the time. How many workers were there in the group?
A
14
B
12
C
10
D
15
Question 40 Explanation: 
Let initially X number of workers be there.

Now, Using work equivalence method,

X + (X-1) + (X-2)+ . . . . + 1 = X *55% of X

[X*(X+1)]/2 = 55X/100

[series is in AP. Sum of AP = {No. of terms (first term+ last term)/2}]

X = 10 workers.

There are 40 questions to complete.

Leave a Reply

Your email address will not be published. Required fields are marked *