A histogram has a bar for the class . The frequency density is 3.2. What is the frequency of this class?
Answer and explanation
Correct answer: B. 16
- Step 1: Frequency = frequency density x class width.
- Step 2: The class width is 25 - 20 = 5.
- Step 3: Frequency = 3.2 x 5 = 16.
Answer
16.
Why not the others: 3.2 is the frequency density itself, 8 uses a class width of 2.5 and 80 multiplies by 25.
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