# Marlo dug a ditch in 30 minutes Maricris, can dig same size ditch in 1 hour. Working together, how long will it take them to dig the ditch?

### 9 Answers

- KrishnamurthyLv 72 years ago
Mario does 1/30 of the ditch in a minute.

Maricris does 1/60 of the ditch in a minute.

Let t = time in minutes

t(1/30) + t(1/60) = 1

t/30 + t/60 = 1

2t/60 + t/60 = 1

3t = 60

t = 20 minutes

Working together, it will take them 20 minutes to dig the ditch.

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- SumDudeLv 72 years ago
3 hours. They will always be getting in each other's way and on each other's nerves.

Source(s): It's a union thing. {Overtime pays time and a half.}- Log in to reply to the answers

- Anonymous2 years ago
as marlo cannot work faster it will take both 30 minutes. it is a trick question which other answers fell for

- SumDudeLv 72 years agoReport
I like that logic. LUNCH BREAK !!!

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- LaurieLv 72 years ago
Mario does 1/30 of the ditch in a minute.

Maricris does 1/60 of the ditch in a minute.

Let t = time in minutes

t(1/30) + t(1/60) = 1

t/30 + t/60 = 1

2t/60 + t/60 = 1

3t = 60

t = 20 minutes

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- Anonymous2 years ago
A problem involving work can be solved using the formula Work Formula, T/A + T/B = 1 where T = time working together, A = the time for person A working alone, and B = the time for person B working alone.

Step 2: Solve the equation created in the first step. This can be done by first multiplying the entire problem by the common denominator and then solving the resulting equation.

Step 3: Answer the question asked of you in the problem and be sure to include units with your answer.

T/30 + T/60 = 1

60(T/30 + T/60 = 1)

60T/30 + 60T/60 = 60

2T + T = 60

3T = 60

T = 20 minutes

your longhand is correct, but an easy guess was 20 minutes ... as in 2/3 + 1/3 ... but I did not want to give a straight answer.

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- -j.Lv 72 years ago
Marlo digs 1/30 of a ditch in 1 minute.

Maricris digs 1/60 of a ditch in 1 minute.

So every minute combined, they dig 1/30 + 1/60 of a ditch. 1/30 is the same as 2/60, so

2/60 + 1/60 = 3/60 of a ditch per minute.

That reduces to 1/20, so they dig 1/20 of a ditch per minute.

That means it takes them 20 minutes to dig the whole ditch. Done.

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- Anonymous2 years ago
One hour, two people work slower and take more breaks

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- Anonymous2 years ago
22.5? I moved you over to mathematics for better answers

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- Elaine MLv 72 years ago
How long is the ditch? Did both work on the same size?

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