If \(1/4, 1/x, 1/10\) are in H.P., what is the value of x?
Answer: B
If the terms are in H.P., their reciprocals (4, x, 10) are in A.P. For an A.P., the middle term is the arithmetic mean of the other two. So, \(x = \frac{4+10}{2} = \frac{14}{2} = 7\).