Coach Pugh has 12 helmets and 8 footballs in his locker room. Which ratio(s) is (are) equivalent to the ratio of helmets to footballs in Coach Pugh's locker room?

129

Step-by-step explanation:

Considering the survey to be representative, you can simply multiply the share of students p preferring “Track & Field” with the whole school population at the same time to estimate the number of such students in the whole school.

First we need to find the relative share p of such answers in the study by dividing it by the sum of answers, assuming that the table is complete for that random sample:

p = 4/(8 + 5 + 4) = 4/17

Then for the whole school we get 550 p ≈ 129.4