Answer:
e. All of the reasons are correct.
Step-by-step explanation:
In most cases, studying all the population is impossible. In other cases, it is too expensive or time consuming.
A sample will give us, in most cases and combined with tools of statistical analysis (hypothesis testing or confidence intervals), enough information to make an unbiased estimation about the characteristic of the population we are studying.
133 adult tickets were sold.
Step-by-step explanation:
Given,
Total tickets sold for school play = 399
Let,
x represent the number of children tickets sold.
y represent the number of adult tickets sold.
According to given statement;
x+y=399 Eqn 1
x = 2y Eqn 2
Putting value of x from Eqn 2 in Eqn 1

Dividing both sides by 3

133 adult tickets were sold.
Keywords: linear equation, substitution method
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This statement is false as all vertical angles are considered congruent but not all congruent angles are considered vertical angles. Any obtuse or acute angle may be considered congruent. If the angle from point A to B is 110 and the angle between B to C is 110 as well then they are congruent