Question

Word Problems Help!

12 men take 6 hours to finish a work. After the 12 men have worked for 1 hour, the contractor decides to call in 8 more men so that the work can be completed earlier. How many hrs would 20 men take to complete the remaining work?

Answer 1

Just a minute please,

Answer 2

@JustinSpeedster you still here?

Answer 3

work = men/hour

\[\frac{ 12 }{ 6 }\]\[\frac{ 12 }{ 6 }\ - \frac{ 1 }{ 5 }\]

is that right?

Answer 4

@Hero sorry for the afk...can you teach me how to solve it? I'm stuck.

Answer 5

The key to solving this Is Keeping track of the total man hours

Answer 6

It takes 12 men 6 hours to complete the Work

Answer 7

multiplying 12 by 6 gets you 72 total man hours necessary to complete the job.

Answer 8

They tell us that the 12 men have already worked 1 hour or 12 man ho urs so We Subtract 12 from 72 to get 60 Man hours remaining

Answer 9

They add eight more men to this project so at that point , we have 20 men and 60 Man hours left to complete the job. How many hours will it take?

Answer 10

I don't get it T.T

Answer 11

5 hours?

Answer 12

At this point you divide 60 by 20 to get the number of hours it will take the 20 men to complete the job.

Answer 13

3 hours

Answer 14

yes three hours, now try to understand the reasoning behind this approach.

Answer 15

why did you multiply 12 by 6?

Answer 16

To Calculate the total man hours necessary to complete the work.

Answer 17

OH I see..I guess it was easy after analyzing it. I feel like a stupid now. The conflict that I encountered was the forming of equation. I failed to calculate the man hours....I was focused on solving the rate on how 1 worker/hour to solve everything. Oh well. Thanks for the help, HERO. Another lesson well taught. :D

Answer 18

I don't like solving it using fractions. That approach is slightly unintuitive.

Answer 19

my first train of thought is to calculate total man hours Instead of rate