Example 5 - Chapter 7 - The Mathematics of Maybe: Introduction to Probability

Transcript

Example 5 We want to know the favorite fruit of all 1,500 students in your school. Asking all 1,500 people is too much work! Instead, you ask a smaller group of 50 students (this is called a sample) Let us assume that the results are: 20 students like mango, 15 students like apples, 10 students like bananas, and 5 students like grapes. Now, Probability students love mangos = (𝑵𝒖𝒎𝒃𝒆𝒓 𝒐𝒇 𝒔𝒕𝒖𝒅𝒆𝒏𝒕𝒔 𝒘𝒉𝒐 𝒍𝒐𝒗𝒆 𝒎𝒂𝒏𝒈𝒐)/(𝑻𝒐𝒕𝒂𝒍 𝑵𝒖𝒎𝒃𝒆𝒓 𝒐𝒇 𝒔𝒕𝒖𝒅𝒆𝒏𝒕𝒔) = 20/50 = 2/5 = 0.4 = 40% We can now use that 40% to estimate the whole school Since 40% of 1,500 = 40/100 × 1,500 = 600 Thus, we can say 600 students have their favourite fruit as mango