Considering the survey to be representative, you can simply multiply the share of students <em>p</em> 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 <em>p</em> of such answers in the study by dividing it by the sum of answers, assuming that the table is complete for that random sample:
<em>p</em> = 4/(8 + 5 + 4) = 4/17
Then for the whole school we get 550 <em>p</em> ≈ 129.4
