Aptitude - True Discount - Discussion
Discussion Forum : True Discount - General Questions (Q.No. 11)
11.
Rs. 20 is the true discount on Rs. 260 due after a certain time. What will be the true discount on the same sum due after half of the former time, the rate of interest being the same?
Answer: Option
Explanation:
S.I. on Rs. (260 - 20) for a given time = Rs. 20.
S.I. on Rs. 240 for half the time = Rs. 10.
T.D. on Rs. 250 = Rs. 10.
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10 | x 260 | ![]() |
= Rs. 10.40 |
250 |
Discussion:
24 comments Page 1 of 3.
Rda said:
3 years ago
Thanks @Wasim Ajaz.
Abi said:
4 years ago
@Smitha.
I am getting 10 as answer.
I am getting 10 as answer.
Smitha said:
4 years ago
T.D = 20
Amount = 260
P.w = Amount - TD = 240.
S.I on p.w = 20.
By formula:
R * T = S.I * 100/p.w = 25/3.
Again by question:
Td = p.w * R * T/100.
Where the Time is half so R*T/2.
i.e 25/6.
We get TD = 10.49.
Amount = 260
P.w = Amount - TD = 240.
S.I on p.w = 20.
By formula:
R * T = S.I * 100/p.w = 25/3.
Again by question:
Td = p.w * R * T/100.
Where the Time is half so R*T/2.
i.e 25/6.
We get TD = 10.49.
(2)
Pavan G J said:
5 years ago
It is correct, just take rt/100 = 1/24.
Shawn Soares said:
5 years ago
How are you all calculate RT to be 1/12, by using TD=PW*(RT)?
Shouldn't the formula be TD=PW*(RT)/100? Which should give RT=100/12?
Shouldn't the formula be TD=PW*(RT)/100? Which should give RT=100/12?
Manish Kumar said:
6 years ago
@Somesh Saurabh,
Your explanation really helped us, but could anyone correct me if im wrong:
that is why divide by 100 is Missing:
i.e, SI = P*R*T/100.
so, SI on TD = (Amount - TD *R*T)/100.
Your explanation really helped us, but could anyone correct me if im wrong:
that is why divide by 100 is Missing:
i.e, SI = P*R*T/100.
so, SI on TD = (Amount - TD *R*T)/100.
Vaishali jagtap said:
7 years ago
I am not getting it. Please help it with the correct explanation.
Wasim Ajaz said:
7 years ago
Here's the correct way,
Td=20,A=260,pw=240,
Td=pw * rt ÷ 100; rt=100/12.
ATQ, time is reduced to half so new time(rt2) will b 100/24.
Td=a * rt2/100+rt2;
Td=(260 * (100/24))÷ (100+100/24) = 10.4.
Td=20,A=260,pw=240,
Td=pw * rt ÷ 100; rt=100/12.
ATQ, time is reduced to half so new time(rt2) will b 100/24.
Td=a * rt2/100+rt2;
Td=(260 * (100/24))÷ (100+100/24) = 10.4.
Deepesh samant said:
9 years ago
As we know rt = 1/12.
Rt/2 = 1/24.
T.d = amount * rt / 100 + rt.
= 260 * 1/24 / 100 + 1/24.
= 10.4.
Rt/2 = 1/24.
T.d = amount * rt / 100 + rt.
= 260 * 1/24 / 100 + 1/24.
= 10.4.
Somesh Saurabh said:
9 years ago
Guys, there is only a little difference between SI and True Discount(TD).
SI is always calculated on the principal amount while TD is always calculated on the PW.
For eg., If the amount g is given as 1000 the SI will be SI = 1000 * R * T.
But for TD, first we need to get PW = (1000 - TD).
Then, TD = (1000 - TD) * R * T.
Hope you guys find it helpful. Thank You.
SI is always calculated on the principal amount while TD is always calculated on the PW.
For eg., If the amount g is given as 1000 the SI will be SI = 1000 * R * T.
But for TD, first we need to get PW = (1000 - TD).
Then, TD = (1000 - TD) * R * T.
Hope you guys find it helpful. Thank You.
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