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nithiu
Group Title
'A' and 'B' can do a piece of work in 25 days and 30 days respectively. Both start the work together but 'A' leaves the work 8 days before its completion. Find the time in which the work is finished.
 one year ago
 one year ago
nithiu Group Title
'A' and 'B' can do a piece of work in 25 days and 30 days respectively. Both start the work together but 'A' leaves the work 8 days before its completion. Find the time in which the work is finished.
 one year ago
 one year ago

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stgreen Group TitleBest ResponseYou've already chosen the best response.3
'A' can do 1/25 job per day 'B' can do 1/30 job per day part of job done in 8 days=8(1/25 + 1/30) part of job done in rest of days (by 'B' alone)=1[8(1/25 + 1/30)] days consumed to finish job by 'B'=(1/25)*[1[8(1/25 + 1/30)]] total days to finish job=8+(1/25)*[1[8(1/25 + 1/30)]]
 one year ago

stgreen Group TitleBest ResponseYou've already chosen the best response.3
do calculations youself>>make yourself useful
 one year ago

Jas9420 Group TitleBest ResponseYou've already chosen the best response.1
Now, the time taken by A and B to complete 22/30th work is \[\frac{ 22 }{ 30 }\times \frac{ 210 }{ 11}\] And for the total, number of days, you'll have to add an 8 it.
 one year ago

sasogeek Group TitleBest ResponseYou've already chosen the best response.0
stgreen, A leaves the job 8 days BEFORE COMPLETION.... not 8 days after they began.... so that's how long they would've taken to finish minus 8... correct?
 one year ago

stgreen Group TitleBest ResponseYou've already chosen the best response.3
oh right i didn't see that
 one year ago

nithiu Group TitleBest ResponseYou've already chosen the best response.0
8/25+1/30=53/150
 one year ago

nithiu Group TitleBest ResponseYou've already chosen the best response.0
153/150=97/150*30
 one year ago

Jas9420 Group TitleBest ResponseYou've already chosen the best response.1
It's 14 + 8 = 22 days, I think.
 one year ago

stgreen Group TitleBest ResponseYou've already chosen the best response.3
if both work they take 14 days to finish
 one year ago

stgreen Group TitleBest ResponseYou've already chosen the best response.3
so A left after 6 days
 one year ago

stgreen Group TitleBest ResponseYou've already chosen the best response.3
'A' can do 1/25 job per day 'B' can do 1/30 job per day part of job done in 6 days=6(1/25 + 1/30) part of job done in rest of days (by 'B' alone)=1[6(1/25 + 1/30)] days consumed to finish job by 'B'=(1/25)*[1[6(1/25 + 1/30)]] total days to finish job=6+(1/25)*[1[6(1/25 + 1/30)]]
 one year ago

stgreen Group TitleBest ResponseYou've already chosen the best response.3
is it done now?
 one year ago

nithiu Group TitleBest ResponseYou've already chosen the best response.0
18/25=17/25
 one year ago

stgreen Group TitleBest ResponseYou've already chosen the best response.3
^what was that??
 one year ago

nithiu Group TitleBest ResponseYou've already chosen the best response.0
a s work for 8 days
 one year ago

Jas9420 Group TitleBest ResponseYou've already chosen the best response.1
Oh, now I get it. No. of days A and B take to do 1 work: 1/25 + 1/ 30 = 11/ 150= 150/11 In one day, B can do : 8/30th of work. So, the remaining work is done by both A and B. The remaining work is : 22/30 Now, the time taken by A and B to complete 22/30th work is :\[ \frac{ 22 }{ 30 } \times \frac{ 150 }{ 11 } = 10 days.\] So, total = 10 + 8 = 18 days.
 one year ago

phi Group TitleBest ResponseYou've already chosen the best response.1
I would use rate * time = "distance" or in this case \[ \frac{\text{jobs}}{\text{day}}\cdot { \text{days} }= \text{# of jobs} \] let T = total number of days for the job. B works for all T days, A works for T8 days we have \[ \frac{1}{25} \cdot (T8) + \frac{1}{30} T = 1 \] multiply both sides by 30*25 to "clear" the denominators \[ 30 (T8) + 25 T= 750 \\ 55T = 990 \\ T= 18 \]
 one year ago
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