### If p varies directly as q and inversely as r, and p = 4 when q = 2 and r = 6, find p when q = 4 and r = 8.

Given values:

- p = 4, q = 2, r = 6

Translation: Combined variation

*p varies directly as q and inversely as r*

- p = kq/r

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- p = kq/r
- 4 = k · 2/6
- 4 · 6 = 2k
- 24 = 2k
- 24/2 = k
- 12 = k

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- p = ?, q = 4, r = 8
- p = 2q/r
- p = 2 · 4/8
- p = 8/8
- p = 1

- The value of p is
**1**.