Eight car dealerships reported the number of cars they sold last month. Car Dealership Number of Cars Sold GMC 84 Chevrolet 81 Nissan 92 Toyota 92 Ford 95 Honda 94 Hyundai 80 Acura 72 What is the upper and lower quartile of this set of data? lower quartile: 80.5 upper quartile: 93 lower quartile: 88 upper quartile: 93 lower quartile: 80.5 upper quartile: 88 lower quartile: 72 upper quartile: 95

lower quartile: 80.5 upper quartile: 93

Step-by-step explanation:

Fro the above question, we are given the following values for the number of cars 8 dealerships sold.

GMC = 84

Chevrolet = 81

Nissan = 92

Toyota = 92

Ford = 95

Honda = 94

Hyundai = 80

Acura = 72

We are told to find the lower and upper quartile of this set of data.

The lower quartile of a data set can be defined as the median( middle number) of the lower half of the data set. The lower quartile is also known or referred to as (Q1).

The lower quartile is also calculated using the formula

Q1 = 1/4(n + 1) th value

Where n is the number of values in the the date set.

The upper quartile of a data set can be defined as the median( middle number) of the upper half of the data set. The lower quartile is also known or referred to as (Q3).

The upper quartile is also calculated using the formula

Q3 = 3/4(n + 1) th value

Where n is the number of values in the the date set.

Step 1

Arrange the data set from the lowest to the highest number

72, 80, 81, 84, 92, 92, 94, 95

Step 2

Calculate the lower Quartile

Q1 = 1/4(n + 1)th value

n = number of values in the data set = 8 values

Q1 = 1/4(8 + 1)th value

Q1 = 1/4(9)th value

Q1 = 2.25th value

This means it is between the 2nd and 3rd value

2nd value = 80

3rd value = 81

(80 + 81) ÷ 2 = 161 ÷ 2 = 80.5

The Lower Quartile (Q1) = 80.5

Step 3

Calculate the lower Quartile

Q3 = 3/4(n + 1)th value

n = number of values in the data set = 8 values

Q3 = 3/4(8 + 1)th value

Q3 = 3/4(9)th value

Q3 = (27/4)th value

Q3 = 6.75th value

This means it is between the 6th and 7th value

6th value = 92

7th value = 94

(92 + 94) ÷ 2 = 186 ÷ 2 = 93

The Upper Quartile (Q3) = 93

Therefore, the Lower Quartile: 80.5 and Upper Quartile: 93

x² + 3x + 7 = 0       [ax² + bx + c]

a = 1

b = 3

c = 7

quadratic formula:

    (+/- is this ±)

plug in the numbers into the variables

your answer is a