Curriculum
Course: Statistics — Third Secondary
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Curriculum

Statistics — Third Secondary

Unit 1: Correlation and Regression

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Unit 2: Advanced Statistical Measures

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Unit 3: Probability

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Unit 4: Random Variables

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Unit 5: The Normal Distribution

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Quiz

Expectation and Variance — Lesson quiz

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  • Questions count: 6
  • Passing grade: 60%
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1.
What is the formula for the expectation of a discrete random variable?
μ = Σ x²
μ = Σ (x + f(x))
μ = Σ f(x)
μ = Σ (x × f(x))
2.
In the experiment of tossing two coins, with X the number of heads, find the expectation μ.
0
1
2
0.5
3.
A variable takes the values 1, 2, 3, 4 with probabilities x ÷ 10 for each value x. Find its variance σ².
3
10
1
2
4.
In the pound game (gain 40 pounds with probability 0.1, loss of 10 pounds with probability 0.9), what is the expectation?
5 pounds
−5 pounds
−4 pounds
0 pounds
5.
If E(X) = 4 and Var(X) = 5, and Y = 3X + 2, find E(Y).
12
10
14
22
6.
If E(X) = 4 and Var(X) = 5, and Y = 3X + 2, find Var(Y).
15
45
9
47
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