8 men and 10 boys do a work in the same days as 4 men and 16 boys do. 1 man and 3 boys start a work

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16 Apr 2014 Solve

8 men and 10 boys do a work in the same days as 4 men and 16 boys do. 1 man and 3 boys start a work to finish it in 40 days. After eighteen days, 9/20th part of the work had been finished. How many boys should be increased to make the work complete in exact time.

OPtion

1) 8
2) 7
3) 6
4) 5
5) 4
6) 3
7) 2
8) 1
9) 0
10) None of these

Solution

In 18 days, (9/20)th part of work is finished
Thus in 1 day, {9/(20*18)}th = 1/40th part of work is finished
Hence in 40 days, work will be complete.
No additional boys are required.

Correct Option: 9 Best Solution (14)

Dr.Dipin Singh   10 years AGO

8 men and 10 boys do a work in the same days as 4 men and 16 boys do. 1 man and 3 boys start a work to finish it in 40 days. After eighteen days, 9/20th part of the work had been finished.

1 man and 3 boys finish 9/20 work it in 18 days.
1 man and 3 boys finish 1 work it in 18*20/9=40 days.
so no additional boys/men are required.

Like? Yes (13) | No (2)  

MD SOHAIL AKHTER   10 years AGO

1 man and 3 boys start a work to finish the work in 40 days.
after 18 days they hv done 9/20th part of work
so 1-9/20=11/20th part of work is left
so they can do it in 22 days

so 0 days extra a boy requires.

Like? Yes (3) | No (1)  

ANUP KUMAR   10 years AGO

1 man and 3 boys start a work to finish the work in 40 days.
after 18 days they hv done 9/20th part of work
so 1-9/20=11/20th part of work is left
so they can do it in 22 days

so 0 days extra a boy requires.

Like? Yes (3) | No (1)  

TUSHAR    10 years AGO

8m+10b=4m+16b;
m=1.5b;
(1m+3b)*18=(9/20)W;
w=180b;
(1m+(3+x)*b)*22=(11/20)*w;
x=0

Like? Yes (3) | No (1)  

MP    10 years AGO

1 man and 3 boys start a work to finish it in 40 days. After eighteen days, 9/20th part of the work had been finished.
Balance 11/20 work will be completed by same workers in 22 days as 1/40 work is completed per day.
so additional zero boys are needed.

Like? Yes (3) | No (2)  

lakshman   10 years AGO

one day work by 1 men ad 3 boys will be=1\40
now in 18 days work is 1\40*18=9\20.
which is exactly the work done by 1 men and three boys.
therefore no need of increment in boys.
ans is zero

Like? Yes (2) | No (1)  

Meena   10 years AGO

As 9/20 work is completed in 18 days,
total work will be completed by same workers in 40 days.
0 boys should be increased.

Like? Yes (3) | No (2)  

Clair Christ D   10 years AGO

works needs to be finished in 40 days.
in 18 days 45 percent completed
so 5 percent works gets cmpleted in 2 days
so remaining 55 can be complted in 22 days with the same number of boys and men . so no extra addition required.

Like? Yes (1) | No   

susmit   10 years AGO

8x + 10y =4x + 16y
2x = 3y
x=3 units/day
y=2 units/day
1 man and 3 boys complete 18 ( 3 + 6 ) units in 18 days = 162 units
162 = 9/20 * total work
360 units = total work
work remaining = 198 units
So,
198 = 22 [ 3 + (3+k)2 ]
9 = 3 + 6 + 2k
k = 0
Hence, option no. 9

Like? Yes (1) | No   

Udhaya kumar   10 years AGO

by solving finally x+3 = 3
hence x=0........... where x = no of boys should increased..

Like? Yes (2) | No (1)  

Ann Theressa   10 years AGO

1 men and 3 boys can finish the work in 40 days

Their 1 day's work = 1/40
18 days work = 18/40 = 9/20

Given in 18 days 9/20th part of work had been finished.

===> 1 men and 3 boys can complete the work in 40 days.

Like? Yes (1) | No (1)  

ASHISH MITTAL   10 years AGO

8m+10b=4m+16b
4m=6b
1m=(3/2)
so 1m+3b=3/2+3=(9/2)b
and equation is
(9/2)*(18/22)*(11/20)*(20/9)=9/2
this is same no of boys who is initially working so no of boys required is=(9/2)-(9/2)=0
and option (9)

Like? Yes (1) | No (1)  

Rashmi bharti   10 years AGO

only 1 man and 3 boys can do the work in 40 days.

Like? Yes (1) | No (1)  

Nitesh Joshi   10 years AGO

since after 18 days finished work is = (9/20)th
therefore effeciency of per day is 9/(20*18)= 1/40
therefore no xtra boy should be required

Like? Yes (1) | No (2)