A can complete a piece of work in 25 days . after working for 5 days , remaining work is completed in 15 days with the help of B . then B can complete the whole work in how many days?
Answers
Step-by-step explanation:
A's 1 day's work =
25
1
Similarly, B's 1 day's work =
20
1
A's and B's together 1 day's work
25
1
+
20
1
=
100
4
+
100
5
=
100
4+5
=
100
9
Their 5 day's work together = 5 x 1 day's work
1−
100
45
=
100
100
−
100
45
=
100
100−45
=
100
55
Now, this remaining work is done by B.
Let B takes x days to complete it.
20
1
×x=
100
55
⇒x=
100
55
×20
⇒x=
5
55
⇒x=11
Hence, B will finish the remaining work in 11 days.
GIVEN:
A can complete a piece of work in 25 days.
A completed 5 days of work, and remaining work done by B in 15 days.
To find:
Number of days taken by B to do the whole work.
Solution:
Rate of work = 1/ Time taken
So, work done by A in 1 day = 1/25
A's work in 5 days = 5 × 1/25 = 1/5
So, B's remaining work = 1 - 1/5 = 4/5
B finished 4/5 work in 15 days.
∴ One day's work for B = 4/5÷15 = 1/75
∴ B can finish the whole work in 75 days