Question

the histogram summarizes the number of tropical storms per year in the us for 30 years. what interval contains the 60th percentile for this data? choose 1 answer:

Explanation:

Step1: Calculate the index

We have $n = 30$ data - points. The index $i$ for the $p = 60$th percentile is $i=\frac{p}{100}\times n=\frac{60}{100}\times30 = 18$.

Step2: Cumulative - frequency calculation

Starting from the left - hand side of the histogram, we calculate the cumulative frequencies:
The first bar (0 - 25) has a frequency of 1.
The second bar (25 - 50) has a frequency of 7, and the cumulative frequency is $1 + 7=8$.
The third bar (50 - 75) has a frequency of 5, and the cumulative frequency is $8 + 5 = 13$.
The fourth bar (75 - 100) has a frequency of 4, and the cumulative frequency is $13+4 = 17$.
The fifth bar (100 - 125) has a frequency of 3, and the cumulative frequency is $17 + 3=20$.
Since the 18th value falls within the cumulative - frequency range when considering the bar with the interval 100 - 125 (as the cumulative frequency reaches 17 before this bar and 20 after it).

Answer:

100 - 125