Suppose a man's scalp hair grows at a rate of 0.32 mm per day. What is this growth rate in yards per hour?

Question

I’m really having trouble with conversions. Can i see steps please so I can actually learn, thank you
how do I convert the days into hours. i am getting stuck there.
I tried dividing the yards by 24hrs and 365*34 but neither are giving me the correct answer

Answer 1

Use dimensional analysis, usually learned in Algebra 2 and used extensively in HS Chemistry, General Chem in College etc. The question gives the growth rate in (mm/day) and asks for the growth rate in (yards/hour.) Add conversion factors to the left side to arrive at yards per hour.



So, 0.32 mm/day = X yards/hour



1) (0.32 mm/day)(day/24 hours) = .013 mm/hour



2) 0.013 mm/hour = X yards/hour



So, (0.13 mm/hour)(meter/1000mm) = .000013 meters/hour



3) Need a conversion factor for meters to yards which is (.9144 meters/yard)



So, (.00013 meters/hour)( yard/0.9144 meters) = .000014217 yards/hour



This is how it would normally be done, difference is due to rounding off above....



(0.32mm/day)(day/24 hours)(1 meter/1000 mm)(yard/0.9144 meters)= .000014582 yards/hour

Answer 2

Do it in two stages, first the distance and then the time.



For the distance, you need to know that there are 25.4 mm in 1 inch and 36 inches in 1 yard, so you first divide the 0.32 by 25.4 to convert to inches and divide the result by 36 to convert the inches to yards. Be warned: the result is a very small number. Call it x.



Now for the time, which is easier. There are 24 hours in a day, so divide x (which is the daily growth) by 24 to get the hourly growth. That's it.

Answer 3

Someone may have already mentioned this but you need to get a regular trim to remove the split ends and such. A lot of people think that cutting your hair will slow down the process. However, having dry/split ends will actually slow down the growing process. Book an appointment with a hair dresser every 6 weeks or so for a trim & style. Your hair will not only look healthier but your hair will not look messy. Believe me - I tried growing my hair too, if you wanna try a product, try this https://www.youtube.com/watch?v=J0R-l34MHOc i used it, works great really.

Answer 4

0.32mm dived by 24 (giving the hourly growth rate in mm) = 0.00133



914.4 millimetres = 1 yard



so divide 0.00133 by 914.4 = 0.0000145815 yds per hr