Rahul can do 2/7 of a certain work in 6 days while suresh can do 3/5 of the same work in 9 days. they started work together but after 7 days Rahul left the work. find in how many days Suresh can complete the remaining work?
Answers
whole work in 21
Suresh 3/5=9
whole work in 15
work together=1/15+1/21=12/105
together 7 days=7*12/105=12/15
work done by 4/5
remaining work 1-4/5=1/5
Suresh done 1/5 work in 1/5*15= 3days
Answer:
3 days
Step-by-step explanation:
To find the number of days Suresh takes to complete the remaining work, we take the whole work as x.
For Rahul,
2/7th of the work is done in = 6 days.
∴ The whole work is done in = 6 ×7/2=21 days.
∴ Work done in 1 day = 1/21 part of the work
For Suresh,
3/5 th of the work is done in = 9 days.
∴ The whole work is done in = 9 ×5/3=15 days.
∴ Work done in 1 day = 1/15 part of the work
Work done by Rahul and Suresh together in 1 day = 1/21+1/15=(5+7)/105=12/105 part of the work
∴ Work done by Rahul and Suresh together in 7 days = 12/105×7=12/15=4/5 part of the work
∴ Work left to be done = 1-4/5=(5-4)/5=1/5 part of the work.
1/5 part of the work is done by Suresh alone.
∴ 1/5 part of the work is done by Suresh in = 1/5÷1/15=1/5×15=3 days.
Hence, Suresh can complete the rest of the work in 3 days.