Principal (P) = Rs 8000

Rate of interest = 9% per annum or 9/2 % per half year

Number of years = 1 year

There will be 2 half years in 1 year.

A = p( 1 + R/100)^{n}

= Rs [800 (1 + 9/200)^{2}]

= Rs [8000 (209/200)^{2}]

= Rs (8000 x 209/200 x 209/200) = Rs 8736.20

C.I. = A − P = Rs 8736.20 − Rs 8000 = Rs 736.20