2018 · Q22
If H is the harmonic mean of P and Q, then the value of H/P + H/Q is
Elementary MathematicsNumber System
- A1
- B2
- CP+QPQ/{P+Q}{PQ}
- DPQP+Q/{PQ}{P+Q}
Explanation
The harmonic mean is H = 2PQ/(P + Q). Then H/P + H/Q = H(P + Q)/(PQ) = 2PQ(P + Q)/((P + Q)(PQ)) = 2. Hence option B.