A bank offers 15% simple interest per annum. A customer deposits Rs. 7200 each on 1st January and 1st July of a year. At the end of the year, the amount he would have gained by means of interest is
1). Rs. 6803
2). Rs.1660.5
3). Rs. 1701
4). Rs. 850
For first half year
Principal = Rs. 7,200
Rate of interest = 15%
As rate is calculated semi annually
Interest = (7200 × 15 × 1)/200 = Rs. 540
For the second half year
Principal = 7200 + 7200 = Rs. 14400
Interest = (14440 × 15 × 1)/200 = Rs. 1080
Total interest = 540 + 1080 = Rs. 1620