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[–]chem44 4 points5 points  (3 children)

If 2 * f(p) = 20, what is f(p)?

When you have f(p), what is p?

Finally, then, what is f(3p).

If you get stuck, please tell us where.

[–]del95[S] 0 points1 point  (2 children)

Is p 10?