Chirag and Bhavesh working together on certain job takes 7½ days to complete it. Chirag alone takes

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22 Sep 2022 Time & Work

Chirag and Bhavesh working together on certain job takes 7½ days to complete it. Chirag alone takes 8 days less than Bhavesh alone takes. In how many days Akash alone can complete the same work, if he is 60% more efficient than Chirag?

OPtion

1) 15
2) 25
3) 12½
4) 18⅘
5) 22½
6) 18⅓
7) 15⅓
8) 7½
9) 6⅖
10) None of these

Solution

Let Bhavesh alone takes 'x' days, then Chirag takes (x-8) days to finish the work.
1 day's work of Chirag and Bhavesh = 1/(x-8) + 1/x = 2/15
⇒ 2x² - 46x + 120 = 0
(2x-6) (x-20) = 0
x=20
.'. Bhavesh takes 20 days and Chirag takes 12 days.
Hence days required by Akash = (100/160)*12 = 7.5
Correct Option 8)

Correct Option: 8 Best Solution (2)

Dr.Dipin Singh   1 year AGO

From given conditions,
Chirag takes 12 days and Bhavesh 20 days to complete the work independently.
Akash takes 12/1.6 = 7.5 days to complete the work alone.

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G.S.Kantharao   1 year AGO

Let Chirag and Bhavesh can do in x,x+8 days
1/x +1/(x+8)=2/15
2x+8/x^2+8x=2/15
x^2-7x-60=0=>x=12
Let Aakash=K
Now 12/K = 160/100=>K=7.5 days
My option is 8 👈

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