SOLUTION: 12 children working 8 hours a day can clean up their school in 5 days, then 8 children working 19 hours a day will clean the school in how many days.
Question 1037630: 12 children working 8 hours a day can clean up their school in 5 days, then 8 children working 19 hours a day will clean the school in how many days. Found 2 solutions by josgarithmetic, ikleyn:Answer by josgarithmetic(39799) (Show Source): You can put this solution on YOUR website! Rate, Time, JOB. The basic rule RT=J, based on rate being , in unit.
N children all working at individual rates R will work at a rate NR.
"Clean their school" is 1 whole job. Put the attention of time on HOURS. Figure the days later.
12 children working 8 hours a day can clean up their school in 5 days, .
then 8 children working 19 hours a day will clean the school in how many days.
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Let t be the number of HOURS.
The system of equations using time t in hours is .
Two expressions which are both equal to 1. ------------60 hours.
Now finish the answer according to the specified 19 hours per day.
, which is THREE days and maybe some either finishing for part of a day, or a bit of "overtime" during the last of the three days. Answer by ikleyn(53763) (Show Source): You can put this solution on YOUR website! .
12 children working 8 hours a day can clean up their school in 5 days, then 8 children working 19 hours a day will clean the school in how many days.
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The equation is
12*5*8 = 8*x*19.
Find x from this equation.
The equation says that he number of man-hours (children-hours) is the same in both cases.
The problem is so simple and the solution is so obvious that the general theory is not required.