A high school has 360 students 1/2 attend the arithmetic club, 5/8 attend the biology club and 3/4 attend the chemistry club. 3/8 attend all 3 clubs. If every student attends at least one club how many students attend exactly 2 clubs. Select:
A) 45  B) 40  C) 35  D) 50  E) 55
Basically, this question is asking you to figure out how many students are being double-counted.   A-Club has 180 members (1/2 of 360)   B-Club has 225 members (5/8 of 360)   C-Club has 270 members (3/4 of 360)   We can create an equation to solve this:   180+225+270 = n + x + 2y   where n is the number of students, x is the number of students in two clubs, and y is the number of students in three clubs.   The question provides y for us (135).   180+225+270 = 360 + x + 270   x = 405-360= 
<gadget id="calculator">405-360</gadget>
<output>45</output>
45   45
<result>A</result>
A high school has 360 students 1/2 attend the arithmetic club, 5/8 attend the biology club and 3/4 attend the chemistry club. 3/8 attend all 3 clubs. If every student attends at least one club how many students attend exactly 2 clubs.