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.
 T.D. on Rs. 260 = Rs. |
 |
10 | x 260 |  |
= Rs. 10.40 |
| 250 |
Discussion:
24 comments Page 2 of 3.
Puzeetha said:
10 years ago
Please explain in detail.
Matlub Sheikh said:
10 years ago
What is SI? Please any one can explain?
Poonam yadav said:
9 years ago
I am unable to understand these type of questions. Can anyone please explain more?
Somesh Saurabh said:
9 years ago
It's very simple.
This kind of situations when we take credit from some bank.
For e.g., let's say I have taken an amount of X i.e. Present Worth(P.W.).
Now I have promised to bank that I am going to pay the amount in T years. So they will tell directly about the total amount I need to pay after T years and this is Total Amount. The Same situation also comes when we sell something to someone who is not able to pay now and instead ask him to pay the amount after some time but at some interest.
For eg. I am to sell my watch at Rs. 1000 to you and you don't have money now to pay so I will tell you to pay rs 1500 after 2 years. It means that PW is 1000 and True Discount is 500.
The rate of interest (R) can be calculated by using simple formula TD = PW * T * R.
P.S. Please go by basics only. Don't use the formulae blindly.
Thank You.
This kind of situations when we take credit from some bank.
For e.g., let's say I have taken an amount of X i.e. Present Worth(P.W.).
Now I have promised to bank that I am going to pay the amount in T years. So they will tell directly about the total amount I need to pay after T years and this is Total Amount. The Same situation also comes when we sell something to someone who is not able to pay now and instead ask him to pay the amount after some time but at some interest.
For eg. I am to sell my watch at Rs. 1000 to you and you don't have money now to pay so I will tell you to pay rs 1500 after 2 years. It means that PW is 1000 and True Discount is 500.
The rate of interest (R) can be calculated by using simple formula TD = PW * T * R.
P.S. Please go by basics only. Don't use the formulae blindly.
Thank You.
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.
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.
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.
Vaishali jagtap said:
7 years ago
I am not getting it. Please help it with the correct explanation.
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.
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?
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