Question: The true discount on a bill due `9` months hence at `16%` per annum is Rs. `189`. The amount of the bill is :
A
`Rs. 1386`
B
`Rs. 1764`
C
Rs. 1575`
D
`Rs. 2268`
Note: Let p.w. be Rs. x.
Then, S.l on Rs. x at `16%` for `9` months
`= Rs. 189.`
`:. x xx 16 xx 9/12 xx 1/100`
`= 189 or x 1575.`
`:. P.W. = Rs. 1575.`
`:. sum due = P.W. + T.D.`
`= Rs. (1575 + 189)`
`= Rs. 1764.`
Question: The interest on Rs.`750` for `2` years is the same as the true discount on Rs.`960` due `2` years hence. If the rate of interest is the same in both cases, it is :
A
`12%`
B
`14%`
C
`15%`
D
`16 2/3%`
Note: S.l. on Rs.`750 T.D. on Rs. 960.`
This means p.w. of Rs.`960. due `2` years hence is `Rs. 750.`
`:. T.D. = Rs. (960 - 750)`
`= Rs. 210.`
Thus, S.l on Rs.`750` for `2` years is Rs.`210`
:. Rate` = ((100 xx 210)/(750 xx 2))%`
`= 14%`
Question: The simple interest and the true discount oa a certain sum for a given time and at a given rate are Rs. `85` and Rs.`80`respectively. The sum is :
A
`Rs. 1800`
B
`Rs. 1450`
C
`Rs.1360`
D
`Rs. 6800`
Note: Sum`= (S.l. xx T.D.)/((S.l.) - (T.D.))`
`= (85 xx 80)/(85 - 80)`
`= Rs. 1360.`
Question: If Rs. `10` be allowed as true discount on a bill of Rs. `110` due at the end of a certain time , then the discount allowed on the same sum due at the end of double the time is :
A
`Rs.20`
B
`Rs. 21.81`
C
`Rs. 22`
D
`rs. 18.33`
Note: S.l. on Rs.`(110 - 10)` for a certain time = Rs.`10`
S.l on `Rs.`100` for double the time `= Rs. 20`
T.D on `Rs. 120 = Rs.(120 - 100)`
`= Rs. 20`
T.D. on ` Rs. 110 = Rs. (20/ 120 xx 110)`
`= Rs. 18.33.`
Question: A man wants to sell his scooter. There are two offers one at Rs.`12000` cash and the other at a credit of Rs. `12880` to be paid after `8` months money being at `18%` per annum. Which is the better offer ?
A
`Rs. 12000` in cash
B
`Rs. 128880` at credit
C
Both are equally good
Note: `p.w. of Rs. 12880`due `8` months hence
`= Rs. [(12880 xx 100)/(100 + (18 xx 8/12)]`
`= Rs. ((12880 xx 100)/(112))`
`= Rs. 11500.
cearly, Rs. `12000` in cash is a better offer.
Question: Goods were bought for Rs.`600` and sold the same day for Rs.`688.50` at a credit of `9` months and thus gaining `2%`. The rate of interest per annum is :
A
`16 2/3%`
B
`14 1/2%`
C
`13 1/3%`
D
`15%`
Note: S.P.`= 102%` of `Rs. 600`
`=Rs. (102/100 xx 600)`
`= Rs. 612`
Now, P.W.`= Rs. 612` and sum
`=Rs. 688.50.`
:. T. D. = Rs. (688.50 - 612)`
`= Rs. 76.50.`
Thus, S.I. on `Rs. 612` for `9` months is `Rs. 76.50.`
:. Rate`= ((100 xx 76.50)/(612 xx 3/4))%`
`= 16 2/3%`.