Question

the frequency distribution below represents frequencies of actual low temperatures recorded during the course of a 31 - day month. use the frequency distribution to construct a histogram. do the data appear to have a distribution that is approximately normal?
class frequency
a 39 - 44 1
b 45 - 50 1
c 51 - 56 5
d 57 - 62 12
e 63 - 68 8
f 69 - 74 2
g 75 - 80 2
choose the correct histogram below
do the data appear to have a distribution that is approximately normal?
a. no, it is completely erratic
b. no, it is not at all symmetric
c. no, it is approximately uniform
d. yes, it is approximately normal

Explanation:

Step1: Analyze the frequency distribution

The frequencies are 1, 1, 5, 12, 8, 2, 2 for classes A - G respectively.

Step2: Recall normal - distribution characteristics

A normal distribution has a bell - shaped curve, symmetric about the mean.

Step3: Check symmetry

The frequencies increase from class A to D and then decrease. But the distribution is not symmetric. For example, the left - hand side (classes A - C) has frequencies 1 + 1+5 = 7 and the right - hand side (classes E - G) has frequencies 8 + 2+2 = 12.

Answer:

B. No, it is not at all symmetric