Question

each summer, track and field athletes from all over the world represent their country by competing in the sekai games. at the end of last years games, the official record - keeper counted the number of gold medals won by each country in that years games. the histogram below summarizes the data. use the histogram to answer each of the questions. (a) how many countries won from 15 to 18 gold medals? (b) how many countries won 14 or fewer gold medals? (c) what is the class width?

Explanation:

Step1: Find number of countries for 15 - 18 gold medals

Read the frequency from the histogram for the 15 - 18 interval. The bar for 15 - 18 gold medals reaches up to 5 on the frequency axis. So the number of countries is 5.

Step2: Calculate number of countries with 14 or fewer gold medals

Add the frequencies of the intervals 3 - 6, 7 - 10, and 11 - 14. The frequency for 3 - 6 is 2, for 7 - 10 is 9, and for 11 - 14 is 6. So $2 + 9+6=17$.

Step3: Determine class width

Subtract the lower - limit of one class from the lower - limit of the next class. For example, taking the classes 3 - 6 and 7 - 10, $7 - 3 = 4$.

Answer:

(a) 5
(b) 17
(c) 4