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The price of a certain product decreased by 60% every year for the pas
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11 Feb 2022, 08:00
11 Feb 2022, 08:00
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Question Stats:
90% (01:51) correct
9% (03:08) wrong based on 21 sessions
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The price of a certain product decreased by 60% every year for the past 4 consecutive years. If the average price of the product was originally $x, what is the average price of the product now in terms of x?
(A) 16x/625
(B) 16x/125
(C) 16x/81
(D) 36x/81
(E) 18x/9
(A) 16x/625
(B) 16x/125
(C) 16x/81
(D) 36x/81
(E) 18x/9
The price of a certain product decreased by 60% every year for the pas
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11 Feb 2022, 19:41
11 Feb 2022, 19:41
2
The avg price = \(x\)
It decreased by \(60\)% each year for \(4\) years so it will be \(40\)% or \(\frac{2}{5}\)th times of the previous price.
Initial price = \(x\)
First year price = \(\frac{2}{5}x\)
Second year price =\( \frac{2}{5} * \frac{2}{5}x\)
Third year price = \(\frac{2}{5} * \frac{2}{5} * \frac{2}{5}x\)
Forth year price = \(\frac{2}{5} * \frac{2}{5} * \frac{2}{5} * \frac{2}{5}x\)
The price \(= \frac{16}{625}x\)
Answer A
It decreased by \(60\)% each year for \(4\) years so it will be \(40\)% or \(\frac{2}{5}\)th times of the previous price.
Initial price = \(x\)
First year price = \(\frac{2}{5}x\)
Second year price =\( \frac{2}{5} * \frac{2}{5}x\)
Third year price = \(\frac{2}{5} * \frac{2}{5} * \frac{2}{5}x\)
Forth year price = \(\frac{2}{5} * \frac{2}{5} * \frac{2}{5} * \frac{2}{5}x\)
The price \(= \frac{16}{625}x\)
Answer A
Re: The price of a certain product decreased by 60% every year for the pas
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08 Mar 2022, 17:22
08 Mar 2022, 17:22
1
If you are not sure how to do the math another way to do this is as follows,
Set x=1000
1000*60% (or 0.6)= 600
1000-600=400 (Year 1 change)
400*0.6=240
400-240=160 (Year 2 change)
160*0.6=96
160-96=64 (Year 3 change)
64*0.6=38.4
64-38.4=25.6(Year 4 change)
Now its just a matter of plugging in your x value (1000) into the answer choices until you get the correct year 4 value
16x/625, plug in 1000 for x= 16000/625 is 25.6 which matches the value we found above.
Set x=1000
1000*60% (or 0.6)= 600
1000-600=400 (Year 1 change)
400*0.6=240
400-240=160 (Year 2 change)
160*0.6=96
160-96=64 (Year 3 change)
64*0.6=38.4
64-38.4=25.6(Year 4 change)
Now its just a matter of plugging in your x value (1000) into the answer choices until you get the correct year 4 value
16x/625, plug in 1000 for x= 16000/625 is 25.6 which matches the value we found above.
