Question

1. what would a histograms shape be called if it has a long tail on the left end most of the data is on the right?

a. left skewed
b. right skewed
c. symmetric
d. uniform

1. a bell - shaped curve indicates what relationship between median and mean?

a. mean < median
b. mean > median
c. mean = median
d. cannot tell

1. calculate the weighted average: homework(weight: 20%): 90, quiz(weight: 30%): 80, test(weight: 50%): 70.

a. 77
b. 79
c. 80
d. 81

1. true or false: multiply each value by its weight, add the results, then divide by the total weight to find the weighted average.

a. true
b. false

1. a student has midterms(weighted 40% each) with scores of 85 and 90. the student also has a final(weighted 20%) with a score of 80. what is the weighted average?

a. 85
b. 86
c. 87
d. 88

Explanation:

Step1: Identify left-skewed histogram definition

A left-skewed histogram has a long left tail, with most data clustered on the right.

Step2: Recognize bell-shaped curve properties

A bell-shaped (symmetric) curve has mean equal to median.

Step3: Calculate weighted average (Q21)

Convert weights to decimals, multiply each score by its weight, sum results.
$\text{Weighted Average} = (0.20 \times 90) + (0.30 \times 80) + (0.50 \times 70)$
$= 18 + 24 + 35$

Step4: Evaluate weighted average rule (Q22)

Weighted average formula: sum of (value×weight), no division if weights sum to 1.

Step5: Calculate student's weighted average (Q23)

Multiply each score by its weight, sum results.
$\text{Weighted Average} = (0.40 \times 85) + (0.40 \times 90) + (0.20 \times 80)$
$= 34 + 36 + 16$

Answer:

1. a. Left Skewed
2. c. Mean = Median
3. a. 77
4. b. False
5. b. 86