Question

There are 2.54 cm in an inch.

There are 2.2 lbs. in a kg.

1. Missy knows she is five pounds over a healthy weight. If she is 5’11” how much does she weigh?

2. Ralph is 6’7” and looks very lanky and thin. He only weighs 167 lbs and his mother is worried for his health that he’s far too skinny. Should she be worried? Why or why not?

3. Cindy, Markus and Jane are all the same height and weigh 114lbs, 152lbs and 165lbs respectively. If Marcus is the only one of the three with an acceptable BMI then how tall are all three siblings? (There is a range of possible heights. Please answer in feet and inches.)

4. Carol’s BMI is 4 points higher than her brother’s who is on the upper limit of the acceptable range. If they both weigh the same but her brother is 6 feet tall, how tall is Carol? Round to the nearest inch.

5. Angus and Shannon are categorized as obese according to their BMIs. In reality, these two are extremely healthy. What are some possible reasons for the misleading BMIs? (One explanation for each person.)

Answer 1

Use BMI = body mass index:

BMI (USA units) = 703 * weight in b / (heihg in in)^2

1. Missy knows she is five pounds over a healthy weight. If she is 5’11” how much does she weigh?

Total height in inches = 5*12 + 11 = 71 in

assume healthy BMI = 24.9 max

so

24.9 = 703 (mass) / (71^2)

mass = 24.9*(71^2)/703 = 178.550 lb

plus 5 lb extra

mass = 178.550+5 = 183.55 lb

2. Ralph is 6’7” and looks very lanky and thin. He only weighs 167 lbs and his mother is worried for his health that he’s far too skinny. Should she be worried? Why or why not?

Total H = 6*12 + 7 = 79 in

Mass = 167

BMI = 703 * 167 / 79^2 = 18.8112

he is slightly in the limit --> 18.5 will be considered initial limit of underweight, he should be worried in not losing weight