Question: If the difference between the compound interest, compounded half yearly and the simple interest on a sum at `10%` per annum for one year is Rs.`25`,the sum is :
A
B
C
D
`Rs. 9000`
B
`Rs. 9500`
C
`Rs. 10000`
D
`Rs. 10500`
Note: Let the sum be Rs.x. Then,
C.I.`= x (1 + 5/100)^2 - x`
`= ((441x)/400 - x)`
`= (41x)/400`
S.I.`= (x xx 10 xx 1)/100`
`= x/10`
(C.I) - (S.I)`= (41x)/400 - x/10`
`= x/400`
`:. x/400 = 25`
`or x 10000`.