Dear Students and Engineers
This is the second challenge from a series challenges for our beloved students and Engineers
Challenge 2:
A civil Engineer designed a great wall for two equal sides of a town for safety reasons. It was estimated that both sides can be finished in (183 days) if (37 workers) worked for (12 hours) each day. later it was found that (40 volunteers) from the Town asked to join the workers to work for (6 hours) each day until the first side of the town will be finished.
The Question is: How many days (Day: Hour) it will take to complete both wall sides from the beginning until the end?
[toggle title=”Answer & Explanation” state=”close”]Answer: (150 Days: 11 Hours)
As there are two equal sides of the wall, working days will be divided by both sides equally (183/2 = 91.5 days) for each side, as during constructing the second side of the wall there will be no volunteer it means it will remain the same, only first side of the wall will be under the construction by (37 workers for 12 hours & 40 volunteers for 6 hours), If 40 works for 6 hour it means 20 for 12 hours (40*6/12 = 20), it concludes that 37+20 = 57 workers and volunteers work for 12 hours, the difference ratio with the estimated time will be (((57-37)/57) *100 = 35%), This means the volunteers will reduce almost (35 %) of the time (for first wall side). Total time for the first side wall = 91.5 days Total reduced time = (35/100) * 91.5 = 32.1 days Total remained time to finish the first side = 91.5-32.1 = 59.4 days Total time to finish both sides of the wall = 59.4+91.5 = 150.9 days 150 working days and 0.9 of a working day (which a working day = 12 hours) it’s (0.9 *12 = 10.8 hours = 11 hours) [/toggle]
