If the 45 men can do a work in 20 days. Then how many men can do the same work in 75 days?
Answers
Answer:
45 men can complete a work in 16 days
Step-by-step explanation:
40 men can complete the work in 18 days.
=> 1 man can complete the work in 18 X 40 = 720 days.
In one day, the amount of work can be completed by one man = 1/720th
Now, 40 men worked for 8 days.
=> The amount of work complete in 8 days = 40 x 8 X 1/720 = 4/9th.
Amount of work left = 5/9th.
10 more men joined. so total men will be 40 + 10 = 50.
=> Amount of work can be done by 50 men in one day = 50/720 = 5/72.
=> No. of day to complete remaining work = 5/9 X 72/5 = 8 days.
8 days will be required to complete the remaining work by 50 men after the 40 men work for 8 days.
A can do a piece of work in 12 days and B can do it in 18 days. They work together for 2 days and then A leaves. How long will B take to finish the remaining work?
A and B complete 1/12 and 1/18 of work respectively in 1 day.
They complete (1/12 + 1/18) or 5/36 of work together in 1 day.
Working together for 2 days, they complete 2 × 5/36 or 5/18 of work.
After A leaves, B is left with 1-5/18 or 13/18 of work.
As B completes 1 work in 18 days, he'll take 13/18 × 18 or 13 days to complete remaining 13/18 work.
Ans: 13.
12 men can complete a job in 18 days. Six days after they started the work, 4 more men joined them. How many days will they now take to finish the remaining work?
Time taken by 12 men to complete the job =18days
Work done by 12 men in one day =118
Work done by 12 men in 6 days =118×6=13
Work left =1−13=23
Work done by 1 man in one day =112×18=1216
Work done by 16 men in one day =1216×16=454
Time to complete remaining work =23÷454=9days
12 men or 30 boys can do a work in 72 days. How many days will 12 men and 30 boys do the same work?
Here 12 men = 30 boys.
Take ratio of efficienies i.e M:B = 5:2 let me tell what exactly it means, when a boy do 2 units of work instead certain time one man can do 5 units of work.
Let's verify that..,
Amount of work done by 12 men in one day = 12*5 = 60 units. Amount of work done by 30 boys in one day = 30*2=60
So total work done by either men team or boys team in 72 days is 60*72 = 4320 units
When men and boys work together they will do 120 units of work per day. Hence number of days required is 4320/120 = 36 days
Or else it is simple when you notice that working efficiency is doubled due men and boys are working together hence time required must be half of the time in first case which is 76/2 =36 days
Thank you
Jai Hind
10 women can complete a work in 7 days and 10 children take 14 days to complete the work. How many days will 5 women and 10 children take to complete the work?
Let women =W, children= C
10W× 7= 10C×14
W:2C
W/C=2/1—eq(i)
10W×7=(5W×10C)x
Let x be the number of days required
So from eq(i)
10×2×7= (5×2+10×1)x
140=20x
x=7 days
If 15 men working 6 hours per day can complete a piece of work in 16 days, in how many days will 10 men complete the same work by working 8 hours per day?
15 men work for 16×6 hours.
1 man takes 16×6×15 hours.
Now, taking the other situation:
Suppose 10 men take 'x' days to complete the work, therefore, 10 men work for 8x hours.
1 man takes 10× 8x hours.
Using the ratio method, we have,
x = (16×6×15)÷(10×8)=18 days.
20 Men can do a piece of work in 18 days. They worked together for 3 days, then 10 men joined them. In how many more days is the work completed?
20- men can do a work in = 18 days
In 1- day 1- man can do= 1/360 work
20 men in 3-days can do=(20x3)/360 =1/6 work.
The remaining 5/6 work will be done by (20+10)= 30- men in= 5/6÷(30/360)
= (5/6)x (12/1)= 10- days.
So in 10- more days the remaining (5/6) - work will be completed.
20 men can complete a piece of work in 25 days. They started the work, and after 5 days, 5 more men joined them. How many days will the work be completed?
The work can be done in =20 x 25 =500 man-days.
In 5- days (5 x 20) = 100 man- days of work was done.
The remaining (500–100)= 400- man-days of work will be done by (20+ 5)= 25- men in = 400/25= 16- days.
So totally the work will be completed in = (5+16)= 21- days.
If 36 men can finish work in 20 days, in how many days can 40 men do the same work?
let say work = 720
and 36 men take 20 days to complete 720
36 * 20 =720
Using x as unknown days, then 40 men take
40 * x = 720
divide both sides by 40
you get x = 18
Therefore 40 men would take 18 days to do the same work.
18 men can do a job in 30 days. After 8 days, there are only 9 men left. In how many days will the remaining work be completed?
18 men need 30 days to finish, so each man does 1/18 x 1/30, or 1/540th of the work per day. After 8 days, 18 x 8/540, or 4/15 of the work is done, leaving 11/15ths unfinished. So 11/15 / 9/540=11 x 540/15 x 9=44 additional days to finish the work
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45 men can complete a work in 16 days. Six days after they started working, so more men joined them.