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aashu4uiit
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In a certain accounting class of 90 students 70% of the students took 13 Nov 2014, 06:07
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B
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80% (02:23) correct 20% (02:36) wrong based on 446 sessions

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In a certain accounting class of 90 students, 70% of the students took the final exam on the assigned day while the rest of the students took the exam on a make-up date. If the students on the assigned day had an average score of 65%, and the students on the make-up date had an average score of 85%, what was the average score for the entire class?

A. 68%
B. 71%
C. 73%
D. 75%
E. 79%
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B
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In a certain accounting class of 90 students 70% of the students took 14 Nov 2014, 00:54
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aashu4uiit
In a certain accounting class of 90 students, 70% of the students took the final exam on the assigned day while the rest of the students took the exam on a make-up date. If the students on the assigned day had an average score of 65%, and the students on the make-up date had an average score of 85%, what was the average score for the entire class?

A. 68%
B. 71%
C. 73%
D. 75%
E. 79%
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As others explained B is the right answer.
But one thing to note, the number of total students is irrelevant since we only deal with 70% students on day 1 and 30% and day 2.
So to ease with calculations we can say there are 100 students with 70 on day 1 and 30 on day 2. Average = (70*65+30*85)/100 = 71.
Slightly easy calculation. :)
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In a certain accounting class of 90 students 70% of the students took 13 Nov 2014, 06:30
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aashu4uiit
In a certain accounting class of 90 students, 70% of the students took the final exam on the assigned day while the rest of the students took the exam on a make-up date. If the students on the assigned day had an average score of 65%, and the students on the make-up date had an average score of 85%, what was the average score for the entire class?

A. 68%
B. 71%
C. 73%
D. 75%
E. 79%
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70% of the students took the final exam on the assigned day --> 0.7*90 = 63 students took the final exam on the assigned day, with an average score of 65.

The rest of the students took the exam on a make-up date --> 90 - 63 = 27 students took the exam on a make-up date, with an average score of 85.

(Average Score) = (Sum of the scores)/(Total students) = (63*65 + 27*85)/90 = 71.

Answer: B.
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In a certain accounting class of 90 students 70% of the students took 14 Nov 2014, 00:18
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Average \(= \frac{63 * 65 + 27 * 85}{90} = 45.5 +25.5 = 71%\)

Answer = B
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In a certain accounting class of 90 students 70% of the students took 17 Nov 2014, 08:20
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Total students 90
% of students appear in exam on assigned date 70% & average score 65%
% of students appear in exam on make up date 30% & average score 85%

average score of entire class =(65+85)/2=75 when no. of students appeared in the exam that happened on different dates.
since here ratio is uneven and weight of students is more concentrated on the score of 65%
This further shows that the average score for entire class must be below 75%.
So, we can minimize the answer choices to option A,B & C whereas to get the exact value one needs to solve it.

From here we have to solve it :
since we have the ratio given (students appear on assigned date)/(students appear on assigned date)=7/3

Average score for entire class =(7*65+3*85)/10 =(455+255)/10=710/10=71

Answer is B
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In a certain accounting class of 90 students 70% of the students took 06 Jun 2017, 15:31
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Bunuel
aashu4uiit
In a certain accounting class of 90 students, 70% of the students took the final exam on the assigned day while the rest of the students took the exam on a make-up date. If the students on the assigned day had an average score of 65%, and the students on the make-up date had an average score of 85%, what was the average score for the entire class?

A. 68%
B. 71%
C. 73%
D. 75%
E. 79%


70% of the students took the final exam on the assigned day --> 0.7*90 = 63 students took the final exam on the assigned day, with an average score of 65.

The rest of the students took the exam on a make-up date --> 90 - 63 = 27 students took the exam on a make-up date, with an average score of 85.

(Average Score) = (Sum of the scores)/(Total students) = (63*65 + 27*85)/90 = 71.

Answer: B.
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Bunuel I understand clearly that this is the formula- but are we supposed to be able to multiply and divide those numbers in under 3 minutes? Is there a shorter method?
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In a certain accounting class of 90 students 70% of the students took 19 Jun 2017, 22:25
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aashu4uiit
In a certain accounting class of 90 students, 70% of the students took the final exam on the assigned day while the rest of the students took the exam on a make-up date. If the students on the assigned day had an average score of 65%, and the students on the make-up date had an average score of 85%, what was the average score for the entire class?

A. 68%
B. 71%
C. 73%
D. 75%
E. 79%
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For this question just attack the stem with pure arithmetic- really the important thing in this question is just knowing how to establish the numerator ( the total number of scores from students who took the exam on both assigned days and make up days)

average= sum/ # items

65 = x/63
65 x 63 = x

85= y/27
85 x 27 =y

[65 x 63] +[85 x 27] / 90 = 71
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In a certain accounting class of 90 students 70% of the students took 20 Jun 2017, 19:14
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aashu4uiit
In a certain accounting class of 90 students, 70% of the students took the final exam on the assigned day while the rest of the students took the exam on a make-up date. If the students on the assigned day had an average score of 65%, and the students on the make-up date had an average score of 85%, what was the average score for the entire class?

A. 68%
B. 71%
C. 73%
D. 75%
E. 79%
Show more

Since 70% of the students took the exam on the assigned day, 0.7 x 90 = 63 students took the exam on the assigned day and 90 - 63 = 27 students took the exam on the make-up day.
The average score for the students on the assigned day was 65% and the score for those on the make-up day was 85%. We can now determine the overall weighted average score:

[63(65) + 27(85)]/90 = (4095 + 2295)/90 = 6390/90 = 71

Answer: B
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In a certain accounting class of 90 students 70% of the students took 20 Jun 2017, 23:44
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B

Average Score (63*65 + 27*85)/90 = 71
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In a certain accounting class of 90 students 70% of the students took 12 Aug 2019, 11:03
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everyone here is working too hard..
65--x---85
ratio is 3/7, difference is 20, hence 3x+7x=20, x=2
65+3x=65+3*2=71
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In a certain accounting class of 90 students 70% of the students took 23 Feb 2026, 12:34
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