SOLUTION: A does 80% of a work in 20 days. He then calls in B and together they finish the remaining work in 3 days. How long B alone would take to do the whole work.
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-> SOLUTION: A does 80% of a work in 20 days. He then calls in B and together they finish the remaining work in 3 days. How long B alone would take to do the whole work.
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Question 875164: A does 80% of a work in 20 days. He then calls in B and together they finish the remaining work in 3 days. How long B alone would take to do the whole work. Answer by dkppathak(439) (Show Source):
You can put this solution on YOUR website! A does 80% of a work in 20 days. He then calls in B and together they finish the remaining work in 3 days. How long B alone would take to do the whole work.
A completed 80% work in 20 days
A can complete the full work in 25 days
A 1 day work will be =1/25 parts
task complete by A in 20 days =80/100 =4/5
remaining work =1-4/5 =1/5 (1)
let b can complete full work in X days
B 1 day work will be =1/X part
A and B 1 day work together will be = 1/25+1/x
= X+25/25X
A and B 3 days work will be = 3(x+25)/25x (2)
by given conditions equation 1 and 2 will be equal
1/5=3x +75/25x
25X = 5(3X +75)
25x= 15X + 375
25x-15x =375
10 X=375
X=37.5 days
B alone can complete whole work in 37.5 days OR 75/2 days Answer