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AnkitK
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Average of money that group of 4 friends pay for rent each month is $8 15 Jun 2011, 08:52
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C
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81% (01:53) correct 19% (02:15) wrong based on 284 sessions

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Average of money that group of 4 friends pay for rent each month is $800. After one persons rent is increased by 20% the new mean is $850. What was original rent of friend whose rent is increased?

A. 800
B. 900
C. 1000
D. 1100
E. 1200
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C
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sudhir18n
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Average of money that group of 4 friends pay for rent each month is $8 15 Jun 2011, 10:34
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AnkitK
Average of money that group of 4 friends pay for rent each month is $800.After one persons rent is increased by 20% the new mean is $850.What was original rent of friend whose rent is increased?
A.800
B.900
C.1000
D.1100
E.1200
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C

0.2X = 4(850-800)
0.2X = 200
X = 1000
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amit2k9
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Average of money that group of 4 friends pay for rent each month is $8 16 Jun 2011, 00:06
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increased amount = 850*4
= 200.

thus 20% of x = 200 means x = 1000 is the original rent.
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Madhavi1990
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Average of money that group of 4 friends pay for rent each month is $8 13 Dec 2017, 15:46
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After one persons rent is increased by 20% the new mean is $850.What was original rent of friend whose rent is increased?

Doesn't the question ask for original rent?New rent after increase of 20% is 1000.

Would like some clarity, thank you
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Average of money that group of 4 friends pay for rent each month is $8 13 Dec 2017, 20:51
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Madhavi1990
After one persons rent is increased by 20% the new mean is $850.What was original rent of friend whose rent is increased?

Doesn't the question ask for original rent?New rent after increase of 20% is 1000.

Would like some clarity, thank you
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Average of money that group of 4 friends pay for rent each month is $800. After one persons rent is increased by 20% the new mean is $850. What was original rent of friend whose rent is increased?

A. 800
B. 900
C. 1000
D. 1100
E. 1200

Average of money that group of 4 friends pay for rent each month is $800 --> the total amount paid by 4 friends = 4*800 = 3200.

After one persons rent is increased by 20% the new mean is $850 --> NEW total = 4*850 = 3400.

The difference = 3400 - 3200 = 200.

This amount is due to one persons rent increase by 20%, so 200 is 20% of that person's rent x*0.2 = 200 --> x = 1000 (original rent of that person was $1000 and after the increase of 20% it became $1200).

Answer: C.

Hope it's clear.
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Average of money that group of 4 friends pay for rent each month is $8 20 May 2024, 11:30
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1. Since 20% increase in rent of one person increases the average by 50 i.e. 850-800, there must have been an increase of 200 in sum of the rent they pay. (50*4)

20% of x=200, x=1000.

2. Assuming each of them pay equal rent at start i.e. 800, 800, 800, 800. (Balancing)
We can determine that one person is paying more than 3 remaining people as avg value increases with 20% increase. To bring the average to 850 at this person is pay extra 200 (+50 increase for all 4 people-> same as above balancing).
Therefore, 800+200=1000

Hence, C­
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