Question

Last week 3/5 of the students in mr.zankers class went on a field trip 7/10 of the students in mr haynes class went what is the average fraction of the students in the two classes who went on the field trip

Answer 1

`((3)/(5)x + (7)/(10)y)/(x + y)`

where x = number of students in Zankers class and y = number of students in Haynes' class

If the number of students in these classes are equal then the average fraction is 13/20

Explanation:

Let x = number of students in Zanker's class

Then number of students who went for the trip is
`(3)/(5)x`

Let y be the number of students in Haynes' clas

Number of students who went =
`(7)/(10)y`

Total number of students who went on the trip =
`(3)/(5)x + (7)/(10)y`

Total number of students in both classes = x + y

So average fraction

=
=
`\frac{\textsf {Total Number of Students On Trip}}{\textsf {Total Number of Students}}\\\\= ((3)/(5)x + (7)/(10)y)/(x + y)`

Without knowing how many students are in each class we can only come up with an equation

If we assume the same number of students in each class
Then we get total students who went on trip =
`(3)/(5) N + (7)/(10)N`
`= \left( (3)/(5) + (7)/(10)\right)N= \left((13)/(10)\right)N`

where N = total number of students

Since the total in 2 classes is 2N the average fraction

`= \left((13)/(10)\right)N / 2N = (13)/(20)`