Elitmus
Exam
Numerical Ability
Time and Work
P can finish a work in 18 days. Q can finish the same work in 15 days. Q worked for 10 days and left the job. how many days does P alone need to finish the remaining work?
Options
1) 8
2) 5
3) 4
4) 6
Read Solution (Total 20)
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- A simple way to solve this kind of problems :-
Suppose p can do it in x days and we already know dat q has worked for 10 days so use this formula -
X/18+10/15=1
Solving this we get x=6 which is required ans.... - 9 years agoHelpfull: Yes(20) No(0)
- q's one day work=1/15
q's 10 day work=10/15=2/3
remaining work=1/3
p's one day work=1/18
so days needed=6
i.e. answer=4) - 9 years agoHelpfull: Yes(12) No(9)
- ans is 6 days
lets assume for P
1 day = 1 unit work
18 day = 18 unit
1 day = 6 hour
then for Q
he can work same amount of work in 15 days, so
15 days = 18 unit
1 day = 18/15 = 6/5;
10 days = 10*6/5 = 12 unit ( 6 unit work remaining)
now p has to work alone for 6 day = 6unit - 9 years agoHelpfull: Yes(3) No(0)
- In one day P works (100/18)% work
and Q does (100/15)% work
In 10 days Q does (200/3)% work so the remaining (100/3)% work is done by P in 6 days
- 9 years agoHelpfull: Yes(1) No(1)
- For this type of problem its always preferred to take total work as the l.c.m. of the no. of days P can finish the work and no. of days Q can finish the work so,
Let total work = 90 units
Then, In one day P does 5 units of work and Q does 6 units of work
Now Q worked for 10 days so work done = 10*6 = 60 units of work
Left work = 90-60= 30 units
So P will take = 30/5= 6 days to do the work
so ans 4) 6 - 9 years agoHelpfull: Yes(1) No(0)
- p 's 1 day work is 1/18 and q's 1 day work is 1/15
both are working together then their one day work is 1/18+1/15=11/90
q work for 10 days then 10 days they are working together then remaining work which is left for p
=1-(11/90*10)=2/9
now using basic rule:
1/18 work done in 1 day
then 2/9 work is 18*2/9=4
- 9 years agoHelpfull: Yes(1) No(0)
- Ans: 4) 6
- 9 years agoHelpfull: Yes(0) No(0)
- Q'S 10 DAYS WORK =10/15=2/3
THEN REST OF D WRK =1/3
P CMPLTED D REMAINING WORK IN 18/3 DAYS MEANS 6 DAYS - 9 years agoHelpfull: Yes(0) No(0)
- ans = 6
( 1 - person who left the work / )*the person who works till end from starting
(1-10/15)*18
= 6 - 9 years agoHelpfull: Yes(0) No(0)
- ((x-n)/x)*Y
where x is the work done by Q
Y is the work done by P
n days Q has worked
solution would be
((15-10)/15)*18 =6 days - 9 years agoHelpfull: Yes(0) No(0)
- B's 10 day's work = (1/15x 10) = 2/3 .
Remaining work = ( 1 - 2/3 ) = 1/3 .
Now, 1/18 work is done by A in 1 day.
Therefore 1/3 work is done by A in ( 18 x 1/3 ) = 6 days. - 9 years agoHelpfull: Yes(0) No(0)
- ANSWER IS 4) 6
- 9 years agoHelpfull: Yes(0) No(0)
- ans is 4 not 6
- 9 years agoHelpfull: Yes(0) No(1)
- Answer is 6
Coz, B's 10 day work = (1/15*10)=2/3
So remaining work =(1-2/3)=1/3
A's one day work = 1/18
therefore 1/3 work's is done by A in (18*1/3) = 6days - 9 years agoHelpfull: Yes(0) No(0)
- 4)6.
take the lcm of 18 and 15=90.
90/18=5 unit per day by p.
90/15=6 unit per day by q.
total unit=90.
in 10 days q will work=10*6=60 unit
remaining work=90-60=30
so p will do the work in 30/5 days=6 days - 9 years agoHelpfull: Yes(0) No(0)
- The answer is 4
work done by Q in ten days = 1/15*10 = 2/3
Remaining work 1-2/3 = 1/3
therefore if P's one day work = 1/18 then P can finish 1/3 work in 1/3*18 = 6days - 9 years agoHelpfull: Yes(0) No(0)
- P can finish desired work in 18 days
Q can finish desired work in 15 days
Total work= 90 unit (LCM of 18 & 15)
P does 5 unit of work/day and Q does it 6 unit/day
Now, after 10 days ,amount of work done=6*10= 60 unit
Remaining work=90-60= 30 unit
Hence ,reuired no. of day in which P can finish the reamaining work=30/5=6 days Answer
After 10 days , amount of work done= 10 - 9 years agoHelpfull: Yes(0) No(0)
- is it really a elitmus qus..its quite easy..
- 9 years agoHelpfull: Yes(0) No(0)
- P can work for 5 units per day
Q can work for 6 units per day
so Q work for 10 days = 6*10= 60 units of work done remaining work 30 units
P does it in 30/5 = 6 days - 9 years agoHelpfull: Yes(0) No(0)
- q '1 day work=1/15 so, q 10 day work=10/15
work left=1-10/15=1/3
1/18 work p finish in =1 day so,
1/3 work p finish in=6 day .ans=option(4) - 7 years agoHelpfull: Yes(0) No(0)
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