P varies directly as q and s but inversely as t and v. P is 360 when...

Question

P varies directly as q and s but inversely as t and v.

P is 360 when q=5, s=7, t=4, and v=6.

Find P=_____ when q=30, s=70, t=50, and v=60.

 

Thank you!

Answer 1

P = kqs/(tv) is the desired formula.

Substitute for P, q, s, t and v--then solve for k.

Finally, substitute everything from the third sentence into the right side, including the above value of k, to compute P.

Now it's easy!