Question 394418
There are 23 students in a homeroom. Eighteen are taking math and 15 taking science. 
Six students are taking math, but not science. 
How many are taking neither subject?
:
18 - 6 = 12 are taking Math & Science
then
15 - 12 = 3 are taking Science only
:
23 - 6 - 12 - 3 = 2 are taking neither
:
Check
M & S = 12
M = 6
S = 3
Neither = 2
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total 23