High School

The table below shows the times taken for a group of athletes to finish a 200 m race.

Work out the percentage of the athletes who took more than 26 seconds to finish the race.

[tex]\[
\begin{tabular}{|c|c|}
\hline
\text{Time, $t(s)$} & \text{Frequency} \\
\hline
22 < t \leq 24 & 3 \\
\hline
24 < t \leq 26 & 5 \\
\hline
26 < t \leq 28 & 8 \\
\hline
28 < t \leq 30 & 9 \\
\hline
\end{tabular}
\][/tex]

Answer :

We are given the number of athletes finishing the race in the following time intervals:

- For [tex]$22 < t \leq 24$[/tex] seconds: 3 athletes
- For [tex]$24 < t \leq 26$[/tex] seconds: 5 athletes
- For [tex]$26 < t \leq 28$[/tex] seconds: 8 athletes
- For [tex]$28 < t \leq 30$[/tex] seconds: 9 athletes

Since we need the percentage of athletes who took more than 26 seconds to finish, we consider the athletes in the intervals [tex]$26 < t \leq 28$[/tex] and [tex]$28 < t \leq 30$[/tex].

1. First, add the frequencies of these intervals:
[tex]$$\text{Number of athletes with } t > 26 = 8 + 9 = 17.$$[/tex]

2. Next, calculate the total number of athletes by summing all the given frequencies:
[tex]$$\text{Total number of athletes} = 3 + 5 + 8 + 9 = 25.$$[/tex]

3. Now, determine the percentage using the formula:
[tex]$$\text{Percentage} = \left(\frac{\text{Number of athletes with } t > 26}{\text{Total number of athletes}}\right)\times 100.$$[/tex]
Substituting the values, we get:
[tex]$$\text{Percentage} = \left(\frac{17}{25}\right) \times 100 = 68.$$[/tex]

Hence, the percentage of athletes who took more than 26 seconds to finish the race is [tex]$$\boxed{68\%}.$$[/tex]