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The rate (initial) of a commodity is 6 lakh..it decreses every year...in frist year the decrease was with the rate of 15% ,then 13.5% the succeeding year and 12% the next year and so on....what will be cost at the end of 10th year.....

rajat

is this the answer

C10 = [ (85)(86.5)(88)................(98.5)(600000) ] / (100)^10

Avinash_Bhat

Now let me put down this in simple language:

1st year : 15% decrease ie, 6 lakh - (15% of 6 lakh) = 510000

2nd year : 13.5% decrease ie, 510000 - (13.5% of 6 lakh) = 429000

Similarily;

3rd year : 357000 4th year : 294000

Now put it like this:

S = 510000 + 429000 + 357000 + 294000 + .......... + T 9 + T 10 -

S = 510000 + 429000 + 357000 + 294000 + ......................... + T 10

0 = (-510000) + (81000 + 72000 + 63000 + .............{9 terms} ) + T 10

T 10 = 510000 - (A.P. of 9 terms whose 1st term is 81000 and 'd' is (-9000))

= 105000. That's the answer, decorder.

IF the answer is wrong, please let me know my mistakes...

IF correct, pleazzzz rate me yaar !!

Thathwamasi

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