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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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

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