super and delux air cooler?

Question

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two types of air-coolers - Super and Deluxe--are made by company ABC...super was introduced in the market in 1996. Due to some defects,one-fourth of the Super air-coolers bought in any year are disposed off as junk after exactly two years from purchase. deluxe air-coolers were introduced in the market in 2002, after retifying these dfects , but still 20% of them had to be disposed off as junk after two years from purchase . the following figures show the number of Super and Deluxe air-coolers in use in the market,from 2000 to 2006, as at the end of each year. it is known that 200 super air-coolers were disposed off in 2002 .


Q: how many Super air-coolers were disposed off in 2004 ?

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funny......no answer no comment please.

BTW,I can provide the answer.....but the answer i did not understand.

my book has given ,

since 200 super air coolers were disposed off in 2002, a total of 600 (2600-2200)+200 Super air coolers were purchased in 2002 . 25% of this =150 were disposed off in 2004.


I DONT understand this above solution.

whythe subtract 2600-2200 ? what that mean s?

>But the statement says that 200 were disposed off in 2002, >hence actually 400+200 coolers were purchased in 2002.

OBJECTION ! ....this 200 were disposed ofin 2002 BUT these are definitely not purchased in 2002 ...why ?

see the statements....

"...Due to some defects,one-fourth of the Super air-coolers bought in any year are disposed off as junk after exactly two years from purchase...."


so this implies these 200 were purchhased 2 years back i.e in 2002-2=2000...is not it ?

Answer 1

The number of coolers disposed off in 2004 will be 25% of the coolers bought in 2002.

So the idea is to find the number of coolers purchased in 2002.

In 2002 2600 air coolers were in use and the year prior to that i.e. in 2001 2200 were in use. So there has been an increase of 400 (2600-2200) coolers in 2002 from 2001. This increase indicates that 400 coolers were purchased in 2002.

But the statement says that 200 were disposed off in 2002, hence actually 400+200 coolers were purchased in 2002.

Hence the answer.

Answer 2

I think insufficient data.

Answer 3

sounds like a homework problem.