Question

question 4 of 18
what is the mean of this data set? if necessary, round your answer to the nearest tenth.
11, 16, 22, 28, 29, 30, 31, 34, 37, 38, 43, 49, 56, 78, 99
a. 50
b. 35.6
c. 45
d. 40.1

Explanation:

Step1: Calculate the sum of data

$$11 + 16+22 + 28+29+30+31+34+37+38+43+49+56+78+99$$
$$=(11 + 99)+(16 + 78)+(22 + 56)+(28 + 49)+(29 + 43)+(30 + 38)+(31 + 37)+34$$
$$=110+94+78+77+72+68+68+34$$
$$=(110+94)+(78+77)+(72+68)+(68+34)$$
$$=204+155+140+102$$
$$=(204 + 155)+(140 + 102)$$
$$=359+242$$
$$=601$$

Step2: Count the number of data

There are \(n = 15\) data points.

Step3: Calculate the mean

The mean formula is \(\bar{x}=\frac{\sum_{i = 1}^{n}x_{i}}{n}\), so \(\bar{x}=\frac{601}{15}\approx40.1\)

Answer:

D. 40.1