HarveyKlaus wrote:

1/4 of all the juniors and 2/3 of all the seniors are going on a trip. If there are 2/3 as many juniors as seniors, what fraction of the students are not going on the trip?

(A) 4/9

(B) 1/2

(C) 2/3

(D) 1/3

(E) 5/6

Pick a number of seniors that is a multiple of 2, 3, and 4.

Let seniors = 12

Juniors = 2/3 of seniors = 8

Total students: 20

Seniors going on trip:

2/3 * 12 = 8

Juniors going on trip:

1/4 * 8 = 2

Total going: (8 + 2) = 10

Total not going: (20 - 10) = 10

Fraction of students not going:

\(\frac{10}{20} = \frac{1}{2}\)

Answer B