Price payable for every Rs.100 (face value) is Rs.121.99. Therefore, for securities worth Rs.10,000, he will have to pay (Price x Face value/100) = 121.99 x 10,000/100=Rs.12,199. Since the coupon on dated GOI securities are payable half yearly, the coupon payment dates for the security are 19 April/ 19 October.
Now if the security was paid for (settled) on December 6, 2001, the accrued interest from the last coupon date to the date of settlement viz. from 19 October, 2001 to December 6, 2001, i.e. for 47 days will be 10.71/100 x 47/360x10000=Rs 139.83.
Hence, the amount payable by the investor will be price plus accrued interest, i.e. Rs12199 +139.83=12,338.83 (if not rounded off).
If the payment is not made on December 6, 2001 but, say, on December 9, 2001, the accrued interest component will be for 50 days instead of 47 days (i.e.3 days more) and it will work out to 10.71/100x50/360 x10,000=Rs.148.75 .The total amount payable by the investor will then be 12,199+148.75=12,347.75 (if not rounded off).