Start with both Math and Science: 3/10
Math only: 11/20
Science only: 5/8
Change to similar fractions. The LCD of denominators 10, 20, and 8 is 40.
Both Math and Science: 3/10 = 12/40
Math only:11/20 = 22/40
Science only: 5/8 = 25/40
To find the number students with their favorites subject/s:
Total Number of pupils surveyed = 40
Both Math and Science = 12 pupils
Math only: 22-12= 10 pupils
Science only: 25-12 = 13 pupils
Total pupils with favorite subjects Math, Science, or both:
12 + 10 + 13 = 35 pupils
40 - 35 = 5 pupils whose favorite subject is neither Math or Science.
As fraction: The part of the total pupils surveyed with their favorite subjects:
Math and Science (Both) = 12/40 or 3/10
Math only = 10/40 or 1/4
Science only = 13/40
Neither = 5/40 or 1/8