Question

Samir can do a job in 15 days and dev can do the same job in 9 days. with the help of Ravi, they did the job in 3 days only. Then, Ravi alone can do the job in​

Answer 1

Answer:

Let the number of days required for Abu to finish the job be x.

Then the number of days required for Babu to finish the job will be x+6.

That is, Abu finishes

x

1

​

part of the job and Babu finishes

x+6

1

​

part of the job in one day.

Thus, they can together finish

x

1

​

+

x+6

1

​

part of the job in one day.

Given that they can together finish the job in 4 days, we have

x

1

​

+

x+6

1

​

=

4

1

​

⇒

x(x+6)

(x+6)+x

​

=

4

1

​

⇒4(2x+6)=x

2

+6x

⇒8x+24=x

2

+6x

⇒x

2

−2x−24=0

⇒x

2

−6x+4x−24=0

⇒(x−6)(x+4)=0

⇒x=6 or x=−4

Here, x is number of days required for Abu to finish the job, so it is not a negative number.

Thus, x=−4 is inadmissible.

Hence, Abu requires 6 days and Babu requires x+6=6+6=12 days to finish the job alone.

Step-by-step explanation:

Pls mark me as brainliest answer of

Answer 2

Answer:

Mark upper one as brainlist plz