I need help with a geometry question. I don't need an answer, just a walk through on how to do it?

Question

The diameters of two water pipes of the same length and 6 in. and 8 in. A single pipe of the same length replaces the two pipes. The single pipe has the same volume as the tow original pipes combined. Find the diameter of the new pipe. - Question. I don't understand how to find the diameter because wouldn't you need the volume of one of the pipes?

Answer

Volume is length times area. They both have the same length, so that does not affect the answer. Area is pi r squared.

A1 = &pi; * 3^2
A2 = &pi; * 4^2
Total area = A1 + A2 = 2&pi; * 9 + 16 = 25&pi;

25pi = &pi; * r^2
25 = r^2
r = 5
d = 10

Answer

Since their lengths are the same,just equate their Ares.
Area of new pipe=area of 2 pipes combined
Pi/2 D^2 =Pi/2 8^2 + Pi/2 6^2
Solve D.
D =10

I need help with a geometry question. I don't need an answer, just a walk through on how to do it?

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