Page 283 - ABCTE Study Guide_Neat

A A lottery

B A census

C A national election

D An internet survey

Answer

Choice A is the correct answer. A lottery uses random sampling. Typically, the winning numbers are
drawn at random from all of the available numbers. Each of the available numbers has an equal chance of
being picked. Choice B is incorrect: A census does not use random sampling, because every member of
the population is included. Choice C is incorrect: A national election cannot use random sampling,
because voting is restricted to only those who are eighteen years of age or older. Choice D is incorrect:
An internet survey does not use random sampling, because members of the sample participate
voluntarily.

Probability

In this section, we’ll explore basic notions of probability of simple and compound events. This exploration
will rely somewhat on counting methods in order to determine sample sizes and the size of outcomes of
experiments.

An event is just an experiment. Rolling a six-sided die, picking a card, and flipping a coin are all events.

The outcome of an event is the result of the experiment. There are six possible outcomes for rolling a die.
There are fifty-two possible outcomes when picking one card from a standard deck of fifty-two cards. And
there are two possible outcomes for flipping a coin.

The probability of an outcome in an experiment is a number, expressed as a ratio, fraction, decimal,
or percent that describes the likelihood that the outcome will occur.

So, you can see that the probability of an outcome is a number between zero and one. Remember, zero =
0%, so if an outcome has a probability of zero, then there is no chance that the outcome will occur. And
one = 100%, so if an outcome has a probability of one, then there is a 100% chance that the outcome will
occur. Probabilities closer to zero are less likely, and probabilities closer to one are more likely.

Question

When one die is rolled, what is the probability that the outcome is even?

A 60%

B 10%

C 50%

D 30%

Answer