Question

Evie was doing a science fair project by surveying her biology class. she found that out of 30 students, 15 had brown hair and 17 had blue eyes and 6 had neither. determine the number of students that had brown hair and blue eyes.

Answer 1

Since there are 6 students with neither brown hair nor blue eyes, the remaining number of students with at least one of the characteristic is 24. The sum of the students with brown hair only, with blue eyes only, and with both should be equal to 24. By letting x be the number of students with both, the equation that would best represent the given is,
                            (15 - x) + x + (17 - x) = 24
 The value of x from the equation is 8.