3. A person\'s body mass index, F, is calculated according to the formula B=703W

Question

3. A person's body mass index, F, is calculated according to the formula

B=703W/H2

where H is the person's height in inches and W is the person's weight in pounds.

Consider this formula to define a surface in a W-H-B coordinate system, with B as the

dependent variable; that is,

B=f(W,H)=703W/H2

(a) Curly is (74 inches tall and weighs 222 pounds. In the direction of which unit

vector (in the W-H plane) would Curly's body mass index decrease most rapidly?

(Round the components of this vector to four decimal places.)

(b) In the direction of which unit vector (in the W-H plane) would Curly's body

mass index stay the same? (You should round the components of this vector to four

decimal places.)

(c) If Curly's height is increasing at the rate of 1 inch per year and his weight is

increasing at the rate of 20 pounds per year, find the rate of change in his body mass

index. (Note that the units for your answer are pounds per square inch, per year.)

Explanation / Answer

a)The bmi formula is actually just weight divided by height. But, for the sake of your formula, you would do this B= (703x222)/(74^2) = 28.5

Related Questions

Navigate

• Browse (All)
• Browse 3
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.