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A group of 20 friends went out for a lunch. Five of them spent $21 eac
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14 Dec 2023, 01:27
14 Dec 2023, 01:27
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41% (02:23) correct
58% (02:16) wrong based on 12 sessions
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A group of 20 friends went out for a lunch. Five of them spent $21 each and the rest spent $3 less than the average (arithmetic mean) of all of them.
A) Quantity A is greater.
B) Quantity B is greater.
C) The two quantities are equal.
D) The relationship cannot be determined from the information given.
Quantity A |
Quantity B |
The average amount spent by all the friends |
$12 |
A) Quantity A is greater.
B) Quantity B is greater.
C) The two quantities are equal.
D) The relationship cannot be determined from the information given.
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Free Materials for the GRE General Exam - Where to get it!!
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Free Materials for the GRE General Exam - Where to get it!!
GRE Geometry Formulas
GRE - Math Book
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A group of 20 friends went out for a lunch. Five of them spent $21 eac
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15 Dec 2023, 10:29
15 Dec 2023, 10:29
2
There are 20 friends total, so there's 15 friends left who spent an unknown amount.
Say x = the average amount spent by all 20 friends. The average formula is (total amount spent by all of them)/(number of friends), so we can set up this equation:
[(number of friends who spent $21 each)(21) + (number of friends who spent x-3 amount)(x-3)]/20= x
\(\frac{5(21) + 15(x-3)}{20} = x\)
\(105+15x-45=20x\)
\(x = 12\)
Say x = the average amount spent by all 20 friends. The average formula is (total amount spent by all of them)/(number of friends), so we can set up this equation:
[(number of friends who spent $21 each)(21) + (number of friends who spent x-3 amount)(x-3)]/20= x
\(\frac{5(21) + 15(x-3)}{20} = x\)
\(105+15x-45=20x\)
\(x = 12\)
Re: A group of 20 friends went out for a lunch. Five of them spent $21 eac
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19 Dec 2023, 15:09
19 Dec 2023, 15:09
1
Average = Sum / Number
A = 105"($21 x 5 spend)" + 15(A-3)"(A-$3 less)" / 20"(total friends)"
20A = 105 + 15A - 45
5A = 60
A = 12
Answer: C) The two quantities are equal.
A = 105"($21 x 5 spend)" + 15(A-3)"(A-$3 less)" / 20"(total friends)"
20A = 105 + 15A - 45
5A = 60
A = 12
Answer: C) The two quantities are equal.
