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May 21st, 2018, 09:16 PM   #1
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How they combine two C I equations in single step?

Naveen lends 30000 to Ravi for 2 years at 20% p.a on compound interest on condition that the interest is compounded half yearly for the first year and compounded annually for the second year. What will be the total interest earned by Naveen at the end of two years?

Solution: 30000 [1+10/100]^2 x [1+20/100] - 30000

= 13560

How they combine two C I equations in single step?

Last edited by skipjack; May 25th, 2018 at 01:00 PM.
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May 22nd, 2018, 03:41 AM   #2
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30000[1+ 10/100]^2 is the principle after the first year- compounded twice at (20%)/2= 10%= 10/100 interest each time. Then (30000[1+ 10/100]^2)(1+ 20/100) is that amount at 20% interest for the second year. Subtracting the original principle, 30000, gives the interest that has accrued.
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May 22nd, 2018, 04:48 AM   #3
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30000(1.10) = 33000
33000(1.10) = 36300 = 30000(1.10)^2
36300(1.20) = 43560
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May 22nd, 2018, 08:03 AM   #4
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Quote:
Originally Posted by Denis View Post
30000(1.10) = 33000
33000(1.10) = 36300 = 30000(1.10)^2
36300(1.20) = 43560
Answer is 13560 not 43560.
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May 22nd, 2018, 08:55 AM   #5
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Well, if you can't see that what I'm showing is
43560 (final amount) - 30000 (start amount) = 13560 (answer),
then you may as well give up on this kind of problem...
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May 22nd, 2018, 08:58 AM   #6
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Quote:
Originally Posted by Denis View Post
then you may as well give up on this kind of problem...
Give up? He never started. It's too easy to just ask for an answer.
Thanks from jonah, Denis, v8archie and 1 others
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May 22nd, 2018, 05:35 PM   #7
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Quote:
Originally Posted by Denis View Post
30000(1.10) = 33000
33000(1.10) = 36300 = 30000(1.10)^2
36300(1.20) = 43560
Tell me how you got 1.10 and 1.20?
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May 22nd, 2018, 05:42 PM   #8
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No.
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May 22nd, 2018, 06:47 PM   #9
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Quote:
Originally Posted by Denis View Post
No.
Why ?
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May 22nd, 2018, 11:49 PM   #10
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Quote:
Originally Posted by Ganesh Ujwal View Post
Tell me how you got 1.10 and 1.20?
In your original post, part of your maths is 1 + 10/100, another part is 1 + 20/100
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