A certain school teaches fourth, fifth. . . . . . . . .

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A certain school teaches fourth, fifth, and sixth grades only, with 150 students in each grade. During one day of a blizzard, 10% of the fourth-grade students, 1/6 of the fifth-grade students, and 60 of the sixth-grade students do not attend school. The student attendance on that day is approximately what percent less than full attendance?

A. 11%
B. 16%
C. 22%
D. 31%
E. 33%

The OA is C.

This exercises with percentages don't like me. I got confused. Experts help. Thanks.
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by Jay@ManhattanReview » Wed Oct 04, 2017 10:01 pm
Vincen wrote:A certain school teaches fourth, fifth, and sixth grades only, with 150 students in each grade. During one day of a blizzard, 10% of the fourth-grade students, 1/6 of the fifth-grade students, and 60 of the sixth-grade students do not attend school. The student attendance on that day is approximately what percent less than full attendance?

A. 11%
B. 16%
C. 22%
D. 31%
E. 33%

The OA is C.

This exercises with percentages don't like me. I got confused. Experts help. Thanks.
We have total number of students in all the three grades = 150*3 = 450

During one day of a blizzard, the number of students who do not attend school is given by

> 10% of the fourth-grade students = 10% of 150 = 15
> 1/6 of the fifth-grade students = 1/6 * 150 = 25
> 60 of the sixth-grade = 60

Thus, during one day of a blizzard, the number of students who do not attend school = 15 + 25 + 60 = 100

The student attendance on blizzard day is (100/450)*100% = 22.22 = ~22% less than full attendance.

The correct answer: C

Hope this helps!

-Jay

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by EconomistGMATTutor » Fri Oct 06, 2017 11:29 am
Vincen wrote:A certain school teaches fourth, fifth, and sixth grades only, with 150 students in each grade. During one day of a blizzard, 10% of the fourth-grade students, 1/6 of the fifth-grade students, and 60 of the sixth-grade students do not attend school. The student attendance on that day is approximately what percent less than full attendance?

A. 11%
B. 16%
C. 22%
D. 31%
E. 33%

The OA is C.

This exercises with percentages don't like me. I got confused. Experts help. Thanks.
Hi Vincen,
Let's take a look at your question.

The question states that A certain school teaches fourth, fifth, and sixth grades only, with 150 students in each grade.
Total students = 150 x 3 = 450

During one day of a blizzard, 10% of the fourth-grade students, 1/6 of the fifth-grade students, and 60 of the sixth-grade students do not attend school.
Let's find the total number of students who do not attend the school.

10% of the fourth-grade students.
=150 x (10/100)
=15 x 1 = 15 students of fourth grade students

1/6 of the fifth-grade students.
= 150 x (1/6)
= 25 students of fifth grade students

60 of the sixth-grade students do not attend school.

Total number of students who do not attend the school = 15 + 25 + 60 = 100 students

Percentage = (100/450) x 100% = 22.22%, that is approximately equal to 22%.
Therefore, Option C is correct.

I am available if you'd like any followup.
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by Scott@TargetTestPrep » Mon Oct 09, 2017 4:15 pm
Vincen wrote:A certain school teaches fourth, fifth, and sixth grades only, with 150 students in each grade. During one day of a blizzard, 10% of the fourth-grade students, 1/6 of the fifth-grade students, and 60 of the sixth-grade students do not attend school. The student attendance on that day is approximately what percent less than full attendance?

A. 11%
B. 16%
C. 22%
D. 31%
E. 33%
Full attendance is 150 x 3 = 450 students.

Because of the blizzard, 0.9 x 150 = 135 fourth graders came to school, (5/6) x 150 = 125 fifth graders came to school, and 150 - 60 = 90 sixth graders came to school. So, 135 + 125 + 90 = 350 students came to school.

Now we can determine what percentage less than full attendance this student attendance is.

(350 - 450)/450 = -100/450 x 100 ≈ -22% = 22% less

Answer: C

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Vincen wrote:
Tue Oct 03, 2017 5:10 pm
A certain school teaches fourth, fifth, and sixth grades only, with 150 students in each grade. During one day of a blizzard, 10% of the fourth-grade students, 1/6 of the fifth-grade students, and 60 of the sixth-grade students do not attend school. The student attendance on that day is approximately what percent less than full attendance?

A. 11%
B. 16%
C. 22%
D. 31%
E. 33%

The OA is C.

This exercises with percentages don't like me. I got confused. Experts help. Thanks.
Full attendance is 150 x 3 = 450 students.

Because of the blizzard, 0.9 x 150 = 135 fourth graders, (5/6) x 150 = 125 fifth graders, and 150 - 60 = 90 sixth graders attend school. So, a total of 135 + 125 + 90 = 350 students attend school.

Since 350/450 = 7/9 ≈ 0.78 = 78%, then the student attendance on that day is approximately 22% less than full attendance.

Answer: C

Scott Woodbury-Stewart
Founder and CEO
[email protected]

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See why Target Test Prep is rated 5 out of 5 stars on BEAT the GMAT. Read our reviews

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