Neco Model Questions Vol1 2020 Mathematics Question 16

Practice objective / multiple choice question 16 from the 2020 Neco Model Questions Vol1 Mathematics examination.

Neco Model Questions Vol1 2020 Mathematics Objective / Multiple Choice Hard Difficulty
Question 16 NECO_MODEL_QUESTIONS_VOL1 • 2020 • MATHEMATICS • objective

Two classes of students sat for the same mathematics test. Class A has 30 students with a mean score of \(68\) and a variance of \(25\). Class B has 20 students with a mean score of \(73\) and a variance of \(16\). Assuming the combined mean of all 50 students is \(70\), calculate the combined standard deviation of the whole group. Give your answer correct to two decimal places.

Answer Options

A. 5.95
B. 6.03
C. 4.87
Correct Answer D. 5.21
Correct Answer
D
Correct Option:
5.21

About This Question

This is Neco Model Questions Vol1 2020 Mathematics Question 16. It is one of the objective questions from the 2020 Neco Model Questions Vol1 Mathematics examination.

Difficulty level: Hard .

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