Question

5 men or 8 boys can do a piece of work in 12 days then 10 men and 2 boys we do the same work in how many days​

Answer 1

If 5 men or 10 boys can do a piece of work in 10 days, in how many days can 10 men and 16 boys do the same work?

As your question reads "5 men or 10 boys" let's set up an equation.

It takes 10 days to complete the work, so each day 10% of work is done.

There are 5 men working, achieving 10% of the total work per day. Each man accomplishes 10/5 or 2% of the work each day.

There are 10 boys working, achieving 10% of the total work per day. Each boy accomplishes 10/10 or 1% of the work each day.

So if there were 1o men [or 10 (.02)] + 16 boys [or 16 (.01)] the equation looks like this

d=days

[10(.02) + 16(.01)]d=1

10*.02= .2

16*.01= .16

.2+.16=.36

.36(d)=1

d=1/.36

Then solve.

d=2.777778

Repeating, I just rounded to 8.

So it takes a little under 3 days

Answer 2

Sᴏʟᴜᴛɪᴏɴ :-

case 1 :- 5 men or 8 boys can do a piece of work in 12 days ..

That Means,

→ 5M = 8B

→ (M/B) = 8/5

Therefore,

→ Total work to be done = 12*5*8 units.

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Case 2 :- 10 men and 2 boys we do the same work in how many days ?

→ (10M + 2B) = ?

→ (10*8 + 2*5) = 80 + 10 = 90 units /day.

Therefore,

→ No. of Days Required = (Total work) / (Per day work) = (12*5*8)/90 = (12*8)/18 = (2*8)/3 = (16/3) = 5(1/3) Days. (Ans.)

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Another Method :-

→ 5M = 8B

Multiply by 2 both sides,

→ 2(5M) = 2(8B)

→ 10M = 16B

So,

→ (10M + 2B) = 16B + 2B = 18B .

Therefore,

→ 8 Boys can do a piece of work in = 12 days.

→ 1 Boy will complete it in = (12 * 8) Days.

→ 18 Boy will complete same work in = (12*8)/18 = (2*8)/3 = (16/3) = 5(1/3) Days. (Ans.)

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