Question

The dot plots show the weights of a random sample of fish from two lakes. Describe the variability of the samples. Make a comparative inference about the fish in the two lakes.
Sample from Lake R
10
11
12
13
14
15
16
17
18
19
20
21
22
Weight (ounces)



A dotplot titled Sample from Lake R has a horizontal axis labeled Weight (ounces) from 10 to 22 in increments of 1. Columns of dots are plotted over horizontal coordinates with heights as follows, where the horizontal coordinate is listed first and the number of dots in the column is listed second: 11, 1; 12, 3; 13, 5; 14, 3; 15, 2; 16, 2; 17, 1; 18, 3; 19, 5; 20, 3; 21, 2.
Sample from Lake S
10
11
12
13
14
15
16
17
18
19
20
21
22
Weight (ounces)



A dotplot titled Sample from Lake S has a horizontal axis labeled Weight (ounces) from 10 to 22 in increments of 1. Columns of dots are plotted over horizontal coordinates with heights as follows, where the horizontal coordinate is listed first and the number of dots in the column is listed second: 15, 3; 16, 4; 17, 6; 18, 5; 19, 3; 20, 5; 21, 4.
.
.
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Question content area right
Part 1
Describe the variability of the samples. Choose the correct answer below.
A.
The variability of the weights of the fish in the two lakes are about the same.
B.
The variability of the weights of the fish in Lake Upper S is greater than the variability of the weights of the fish in Lake Upper R.
C.
The variability of the weights of the fish in Lake Upper R is greater than the variability of the weights of the fish in Lake Upper S.

Answer 1

C. The weights from Lake R are more variable. Lake R ranges from about 11 to 21 ounces (range ≈ 10) and values are spread out, while Lake S is concentrated from about 15 to 21 ounces (range ≈ 6), so Lake R has greater spread.