Help? (1 Viewer)

[chooky_girl26]

Hi i've been tdoing the 2004 paper and i need some help with these two questions..... if someone could help that would be super

A health rating R, is calculated by dividing a person's weight,w, in kilograms by the square of the person's height, h, in metres

I) fred is 150 cm and weighs 72 kf calculate fred's health rating

ii) Over several years, Fred expects to grow 10cm taller. By this time he wants his health rating to be 25. How much weight should he fain or lose to achieve his aim?



b) A set of garden gnomes is made so that the cost ($C) varies directly with the cube of the base length (b centimetres). A gnome with a base length of 10cm has a cost of $50

I) write an equation relating the variable C and b and a constant k

ii) find the value of K

iii) felicity says, 'if you double the base length, you double the cost.' is she correct?

 

[Casmira]

Your first question;

I) firstly figure out hte equation
R = W / H^2
----
W = 72kg
H = 150cm
= 1.5m (H is measured in metres according to question)

R = 72 / 1.5^2
.'. freds health rating is;
R = 32

ii) R = W / H^2
25 = W / 1.6^2
25 = W / 2.56
W = 64kg
'.' fred should loose (72-64) 8kg

See attachment for second question

good luck with the rest of the paper and your studies

 

[chooky_girl26]

thanks u so much xoxox