A can complete a piece of work in 36 days, B in 54 days and C in 72 days. All the three began the work together but A left 8 days before the completion of the work and B 12 days before the completion of work. Only C worked up to the end. In how many days was the work completed?
A
18 days
B
24 days
C
28 days
D
36 days
উত্তরের বিবরণ
Question: A can complete a piece of work in 36 days, B in 54 days and C in 72 days. All the three began the work together but A left 8 days before the completion of the work and B 12 days before the completion of work. Only C worked up to the end. In how many days was the work completed?
Solution:
Let the work be completed in y days. C works for y days
Therefore, A works for (y - 8) days
B works for (y - 12) days.
According to the question,
{(y-8)/36} + {(y - 12)/54} + (y/72) = 1
⇒ 6(y - 8) + 4 (y - 12) + 3y = 216
⇒ 6y - 48 + 4y - 48 + 3y = 216
⇒ 13y = 216 + 96 = 312
⇒ y = 312/13
∴ y = 24
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Updated: 2 weeks ago
Three workers can do a job in 6 days. Two of the workers work twice as fast as the third. How long would it take one of the faster workers to do the job himself?
Created: 2 weeks ago
A
15 days
B
18 days
C
24 days
D
12 days
Question: Three workers can do a job in 6 days. Two of the workers work twice as fast as the third. How long would it take one of the faster workers to do the job himself?
Solution:
Let,
the first and 2nd worker need x days.
Third worker needs 2x days
ATQ,
(1/x) + (1/x) + (1/2x) = 1/6
⇒ (2 + 2 + 1)/2x = 1/6
⇒ 5/2x = 1/6
⇒ 2x = 30
∴ x = 15
So the one faster worker alone will take 15 days to complete the job.
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Updated: 2 weeks ago
A machine produces 240 toys in 4/3 hours. How many toys can it produce in 25 minutes?
Created: 1 week ago
A
60 toys
B
75 toys
C
80 toys
D
90 toys
Question: A machine produces 240 toys in 4/3 hours. How many toys can it produce in 25 minutes?
Solution:
Given,
Time = 4/3 hours = (4/3) × 60 = 80 minutes
In 80 minutes, the number of toys produced = 240
In 1 minute, the number of toys produced = 240/80 = 3
In 25 minutes, the number of toys produced = 3 × 25 = 75
∴ The machine can produce 75 toys in 25 minutes.
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Updated: 1 week ago
A canteen requires 105 kgs of wheat for a week. How many kgs of wheat will it require for 58 days?
Created: 2 weeks ago
A
840 kgs
B
950 kgs
C
620 kgs
D
870 kgs
Question: A canteen requires 105 kgs of wheat for a week. How many kgs of wheat will it require for 58 days?
Solution:
For 7 days it is required = 105 kgs
∴ For 1 days it is required = (105/7) kgs
∴ For 58 days it is required = (105 × 58)/7 = 870 kgs
∴ 870 kilograms of wheat will be required for 58 days.
0
Updated: 2 weeks ago
