True Discount

Question: Goods were bought for Rs. 600 and sold the same 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%

Answer: Option A

Explanation:

S.P. = 102% of Rs. 600 =		102	x 600		= Rs. 612.
		100

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 x 76.50	%	= 16%
		612 x 3 4

Question:
The simple interest and the true discount on 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

Answer: Option C

Explanation:

Sum =	S.I. x T.D.	=	85 x 80	= Rs. 1360.
	(S.I.) – (T.D.)		(85 – 80)

Question:
The true discount on Rs. 2562 due 4 months hence is Rs. 122. The rate percent is:

[A].

12%

[B].

13	1	%
	3

[C].

15%

[D].

14%

Answer: Option C

Explanation:

P.W. = Rs. (2562 – 122) = Rs. 2440.

S.I. on Rs. 2440 for 4 months is Rs. 122.

Rate =		100 x 122	%	= 15%.
		2440 x 1 3

Question:
If the true discount on s sum due 2 years hence at 14% per annum be Rs. 168, the sum due is:

[A].

Rs. 768

[B].

Rs. 968

[C].

Rs. 1960

[D].

Rs. 2400

Answer: Option A

Explanation:

P.W. =	100 x T.D.	=	100 x 168	= 600.
	R x T		14 x 2

Sum = (P.W. + T.D.) = Rs. (600 + 168) = Rs. 768.

Question:
The present worth of Rs. 2310 due 2 years hence, the rate of interest being 15% per annum, is:

[A].

Rs. 1750

[B].

Rs. 1680

[C].

Rs. 1840

[D].

Rs. 1443.75

Answer: Option B

Explanation:

P.W. = Rs.		100 x 2310		= Rs. 1680.
		100 + 15 x 5 2