Question

at the start of the school year, pledmont high surveyed new students about which subject they thought would be the most difficult. the results are shown in the bar graph below. mid - year, 60 new students are taking the survey. based on the information in the bar graph, how many of the new students are more likely to choose physics over algebra as the most difficult subject? a. 7 b. 9 c. 11 d. 18

Explanation:

Step1: Find the number of students for physics and algebra in the initial survey

From the bar - graph, the number of students who thought physics was the most difficult is 70, and the number of students who thought algebra was the most difficult is 45 in the initial survey. The total number of students in the initial survey is \(50 + 70+25 + 45+50=240\).

Step2: Calculate the proportion difference

The proportion of students who chose physics is \(\frac{70}{240}\), and the proportion of students who chose algebra is \(\frac{45}{240}\). The difference in proportions is \(\frac{70 - 45}{240}=\frac{25}{240}=\frac{5}{48}\).

Step3: Apply the proportion to the new - group of students

There are 60 new students. The number of new students more likely to choose physics over algebra is \(60\times\frac{5}{48}=\frac{300}{48}= 6.25\approx 7\).

Answer:

A. 7