Rafi alone can complete a work in 10 days and Tareq alone can complete it in 15 days. Rafi and Tareq undertook to complete the work for Tk. 7500. With the help of Salman, they finished the work in 5 days. How much should Salman be paid?
A
Tk. 1200
B
Tk. 1250
C
Tk. 1300
D
Tk. 1380
উত্তরের বিবরণ
Question: Rafi alone can complete a work in 10 days and Tareq alone can complete it in 15 days. Rafi and Tareq undertook to complete the work for Tk. 7500. With the help of Salman, they finished the work in 5 days. How much should Salman be paid?
Solution:
Rafi's 1 day work = 1/10
Tareq's 1 day work = 1/15
Rafi + Tareq + Salman's 1 day work = 1/5
∴ Salman's 1 day work = 1/5 - (1/10 + 1/15)
= (6 - 3 - 2)/30
= 1/30
Salman's 5 days work = 5 × 1/30 = 1/6
Salman completed 1/6 of the total work.
∴ He should be paid 1/6 of Tk. 7500
∴ Salman’s payment = 7500 × 1/6 = Tk. 1250
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Updated: 1 week ago
A man can do a work in 20 days and a woman in 15 days. If they work on it together for 5 days, then the fraction of the work that is left-
Created: 2 weeks ago
A
8/15
B
1/12
C
5/12
D
None of these
Question: A man can do a work in 20 days and a woman in 15 days. If they work on it together for 5 days, then the fraction of the work that is left-
Solution:
Man's 1 day's work = 1/20
Woman's 1 day's work = 1/15
∴ (Man + woman)'s 1 day's work = (1/20) + (1/15) = (3 + 4)/60 = 7/60
∴ (Man + woman)'s 5 day's work = (7/60) × 5 = 7/12
Thus, Remaining work = 1 - (7/12) = (12 - 7)/12 = 5/12
∴ The fraction of the work that is left = 5/12
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Updated: 2 weeks ago
A man completes 2/5 of a work in 8 days. If his work rate is doubled, how many more days will it take him to finish the remaining work?
Created: 1 week ago
A
3 days
B
6 days
C
4 days
D
8 days
Question: A man completes 2/5 of a work in 8 days. If his work rate is doubled, how many more days will it take him to finish the remaining work?
Solution:
2/5 of the work is done in = 8 days
∴ full work is done in = (8 × 5)/2 days
= 20 days
∴ His daily work rate = 1/20 per day
If his work rate is doubled, his new daily work rate is,
= (1/20) × 2 = 1/10 per day
Remaining portion of the job = 1 - (2/5)
= 3/5
Now,
1/10 work is done in = 1 day
∴ 3/5 work is done in = (3/5) ÷ (1/10) days
= (3/5) × 10
= 6 days
Therefore, it will take him 6 more days to finish the job.
0
Updated: 1 week ago
একটি বাঁধ তৈরি করতে ৩২০ জন শ্রমিকের ২৫ দিন সময় লাগে। ১৬ দিনে বাঁধের কাজ শেষ করতে হলে কতজন অতিরিক্ত শ্রমিক লাগবে?
Created: 3 days ago
A
১২০ জন
B
১৪০ জন
C
১৮০ জন
D
২৪০ জন
প্রশ্ন: একটি বাঁধ তৈরি করতে ৩২০ জন শ্রমিকের ২৫ দিন সময় লাগে। ১৬ দিনে বাঁধের কাজ শেষ করতে হলে কতজন অতিরিক্ত শ্রমিক লাগবে?
সমাধান:
বাঁধ তৈরি করতে,
২৫ দিনে শ্রমিক লাগে= ৩২০ জন
∴ ১ দিনে শ্রমিক লাগে = (৩২০ × ২৫) জন
∴ ১৬ দিনে শ্রমিক লাগে = (৩২০ × ২৫)/১৬ জন = ৫০০ জন
অতএব, অতিরিক্ত শ্রমিক প্রয়োজন হবে = (৫০০ - ৩২০) জন = ১৮০ জন
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Updated: 3 days ago
