The present worth of a bill due 7 months hence is Rs.1200 and if the bill were due at the end of $2\frac{1}{2}$ years its present worth would be Rs.1016. The rate percent is

10% is the right answer

This is the right answer

S.I. = $\large \frac{Principal \times Time \times Rate}{100}$

$ \large 1200 + \frac{1200\times7\times r}{12\times 100}$

Amount (A)

$\large 1200 + 7r = A $.........(i)

$\large 1016 + 25.4r = A$ ...(ii)

$\large  1016 + 25.4r = 1200 + 7r $

$\large  25.4r – 7r = 1200 – 1016$

$\large 18.4r = 184$

$ \large = 10% $ per annum