SOLUTION: I need some help with this problem, please. I'd be grateful. The body mass index,I, can be used to determine an individuals risk of heart disease. An index less then 25 indicates

Algebra ->  Customizable Word Problem Solvers  -> Misc -> SOLUTION: I need some help with this problem, please. I'd be grateful. The body mass index,I, can be used to determine an individuals risk of heart disease. An index less then 25 indicates       Log On

Ad: Over 600 Algebra Word Problems at edhelper.com


    

Question 193262: I need some help with this problem, please. I'd be grateful.
The body mass index,I, can be used to determine an individuals risk of heart disease. An index less then 25 indicates a low risk. The body mass index is given by the formula 700w/H^2, where W= weight in lbs. and H = the height in in.
Jerome is 73 in tall. What weights will keep his body mass index between 19 and 27?
Thanks for your help.
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
I=%28700w%29%2Fh%5E2 Start with the given equation


I=%28700w%29%2F%2873%29%5E2 Plug in h=73 (the given height)


I=%28700w%29%2F5329 Square 73 to get 5,329


Since we want the body index to be in between 19 and 27, this means we must construct the following inequality


19%3C=I%3C=27 ... this says that the body mass index "I" is greater than or equal to 19 AND is less than or equal to 27 (ie it is between 19 and 27)


19%3C=%28700w%29%2F5329%3C=27 Plug in I=%28700w%29%2F5329 (from above)


5329%2A19%3C=cross%285329%29%28700w%29%2Fcross%285329%29%3C=5329%2A27 Multiply ALL sides by 5,329


101251%3C=700w%3C=143883 Multiply


101251%2F700%3C=cross%28700%29w%2Fcross%28700%29%3C=143883%2F700 Divide ALL sides by 700 to isolate w


144.644%3C=w%3C=205.547 Divide


145%3C=w%3C=206 Round to the nearest whole number


So his weight must be within 145 and 206 pounds to have a body mass index between 19 and 27.