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oryanzmommy1
05-11-2006, 10:01 PM
i ran into a problem and i couldnt get it...i was clue less...i dont know how the problem is suppose to be set up or anything...HELP!!! here is the problem it gives me...

Suppose r varies jointly with s and t, and r=180 when s=3 and t=12. Find r when s=8 and t=20

tkhunny
05-11-2006, 10:54 PM
r varies jointly with s and tThese words should ring in your head. Whenever you see them, don't even keep reading the problem. Stop! Write down "r = k*s*t". THEN go back and read the rest of the problem statement.

oryanzmommy1
05-11-2006, 11:31 PM
ok thank you

tkhunny
05-12-2006, 12:20 AM
The next step is to find 'k', the "constant of proportionality". This can be done by substituting all the values given in the problem statement. It MUST give you a complete set.

oryanzmommy1
05-12-2006, 01:13 PM
ok thank you