Question

1
12. 19 men working 7 .5 hours a day can finish a job in 21 days. How many hours a day must
2
45 men work to complete it in 7 days?​

Answer 1

Answer:

5.25 hours per day

Step-by-step explanation:

19 men take 21 days working 7.5 hours per day.

Hours per day 45 men will take to complete in 7 days will be:

if 19 men =7.5 hours

then 45 men = 5.4  hours ( this because the 45 men will take                                                                    less   hours per day, hence you                                                     use the lesser fraction of the two

                                                  values .)

If 21 days =  7.5 hours per day

then 7 days= 21/7   

Therefore the calculation is = 7.5×5.4×21/7

                                              = (7×5×21 )/(5×4×7)

                                              = 735/140

                                              = 5.25 hours per day !!

$MARK \beta rainlist!!$