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# Ratio and Propostion watch

1. Hi, a question and I tried every way that I know to answer but I can't seem to get it right so can anyone help me with this question, please.

M is directly proportional to r^2

When r=2, m = 14

(a) Work out the value of m when r =12
(b) Work out the value of m when m=224
2. m ∝ r^2

m=k r^2

14=k 2^2

14=k 4

14/4=3.5 k=3.5

a) m= 3.5 x 12^2
m= 504

b) do you mean "work out the value of r?"
3. Thank you, I was looking for that answer only and I already worked out r.
4. (Original post by ikraan123)
Thank you, I was looking for that answer only and I already worked out r.
ah okay
5. (Original post by raqeen)
m ∝ r^2

m=k r^2
PLEASE don't post answers - this is against the rules in the maths forum.
6. (Original post by Muttley79)
PLEASE don't post answers - this is against the rules in the maths forum.
s o r r y
I didnt know :-;
7. (Original post by raqeen)
s o r r y
I didnt know :-;
OK - stay around and help but just a hint
8. (Original post by Muttley79)
OK - stay around and help but just a hint
Okay :^_^:

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