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3 years ago

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There are three grades in the school. One grade has 1/3 of the students, one grade has 1/4 of the students. What fraction of stu

dents is in the remaining grade?

1 answer:

AlladinOne [14]3 years ago

4 0

Answer:

Step-by-step explanation:

Let x represent the total number of stdents that has all grades in the school.

There are three grades in the school. One grade has 1/3 of the students, this means that number of students that belongs tho this grade is 1/3 × x = x/3

One grade has 1/4 of the students, this means that number of students that belongs to this grade is 1/4 × x = x/4

Total number of students in both grades would be x/3 +/x/4 = 7x/12

The number of students in the remaining grade would be

x - 7x/12 = 5x/12

fraction of students in the remaining grade would be

(5x/12)/x = 5/12

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$E[X^2]=\displaystyle9\int_0^\infty e^{-y}\,\mathrm dy=9$

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