Using function concepts, it is found that:
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The BMI B, for a person of weight w(in pounds) and height h(in inches) is given by:
[tex]B = \frac{703w}{h^2}[/tex]
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Item a:
To solve the formula for w, we isolate w in the equation above, thus:
[tex]B = \frac{703w}{h^2}[/tex]
[tex]703w = Bh^2[/tex]
[tex]w = \frac{Bh^2}{703}[/tex]
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Item b:
The weight is:
[tex]w = \frac{21.45(64)^2}{703} = 125[/tex]
The weight is of 125 pounds.
A similar problem is given at https://brainly.com/question/5123313