STA108 WEEK 5

LEARNING OBJECTIVE 1:

Measures of Central Tendency (Mean, Median, Mode)

Students need to know how to calculate mean, median, mode for grouped data using function in scientific calculator.

👉🏼 Refer Video 1 above for example with explanation.

👉🏼 Refer Pg.71 (formula and steps to calculate mean, median and mode)

👉🏼 Refer Pg.73 (steps how to use scientific calculator)

👉🏼 Do Example 24 (No. 1, 2, 3) Pg.74 

👉🏼 Do Exercise 2(a) Pg.77

 Answer:  

 Mean =  52.67 (The average Mathematics skill test of students is 56.67 marks)        

 Median = 52.76 (Half of the students score more than 52.76 marks for their Mathematics skill test )

 Mode = 53.03 (Most of the students score 53.03 marks for their Mathematics skill test)

LEARNING OBJECTIVE 2:

Measures of Dispersion (Variance and Standard Deviation)

Students need to know how to calculate measures of dispersion (standard deviation and variance) for grouped data using function in scientific calculator.

👉🏼 Refer Video 2 above for example with explanation.

👉🏼 Watch Video 3 above for more explanation about standard deviation.

👉🏼 Refer Pg.72 (formula)

👉🏼 Refer Pg.73 (steps how to use scientific calculator)

👉🏼 Do Example 24 (No.4) Pg.75

👉🏼 Do Exercise 2(b) Pg.77

Answer:  

Variance = 283.21       

Standard Deviation = 16.83        

LEARNING OBJECTIVE 3:

Measures of Central Position (First, Second and Third Quartile)

Students need to know how to calculate measures of central position (first, second and third quartiles) and for grouped data.

👉🏼 Refer Video 4 above for example with explanation.

👉🏼 Refer Pg.72 (formula).

👉🏼 Do Example 24 (No.6 & 7) Pg.76. 

👉🏼 Do Exercise 2(c) Pg.78

Answer:  

Q1 = 41.12

Q3 = 64.5

LEARNING OBJECTIVE 4:

Measures of Central Position (First, Second and Third Quartile)

Students need to know how to estimate measures of central position (first, second and third quartiles) using ogive.

👉🏼 Refer Video 5 above.

👉🏼 Refer Pg.60 (formula and steps to calculate first, second and third quartiles)

👉🏼 Do Exercise 2(d), (e) Pg.78 --- Estimate all quartiles value, Q1, Q2, Q3 using ogive.

Answer:  

Q1 = 42.5

Q2 = 51.5

Q3 = 64.5

 Minimum score for grade A = 70.5 (find number of top scorer first: 180 - 15% x 180, then find the intersection point from the curve)

Note: You may get different values from mine. It should be no problem, as long as your method is correct and your answer is not too far from mine. Your answer depends on the curve that you drawn too.