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Statistics and probability

Course: Statistics and probability > Unit 7

Lesson 6: Addition rule
Math
Statistics and probability
Probability
Addition rule
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Addition rule for probability (basic)

Google Classroom
One hundred students were surveyed about their preference between dogs and cats. The following two-way table displays data for the sample of students who responded to the survey.
PreferenceMaleFemaleTOTAL
Prefers dogs362056
Prefers cats102636
No preference268
TOTAL4852100
problem 1
Find the probability that a randomly selected student prefers dogs.
Enter your answer as a fraction or decimal.
P, left parenthesis, start text, p, r, e, f, e, r, s, space, d, o, g, s, end text, right parenthesis, equals
  • Your answer should be
  • an integer, like 6
  • a simplified proper fraction, like 3, slash, 5
  • a simplified improper fraction, like 7, slash, 4
  • a mixed number, like 1, space, 3, slash, 4
  • an exact decimal, like 0, point, 75
  • a multiple of pi, like 12, space, start text, p, i, end text or 2, slash, 3, space, start text, p, i, end text

Problem 2
In this sample, are the events "prefers dogs" and "prefers cats" mutually exclusive?
Choose 1 answer:

problem 3
Find the probability that a randomly selected student prefers dogs or prefers cats.
Enter your answer as a fraction or decimal.
P, left parenthesis, start text, p, r, e, f, e, r, s, space, d, o, g, s, space, o, r, space, c, a, t, s, end text, right parenthesis, equals
  • Your answer should be
  • an integer, like 6
  • a simplified proper fraction, like 3, slash, 5
  • a simplified improper fraction, like 7, slash, 4
  • a mixed number, like 1, space, 3, slash, 4
  • an exact decimal, like 0, point, 75
  • a multiple of pi, like 12, space, start text, p, i, end text or 2, slash, 3, space, start text, p, i, end text

problem 4
In this sample, are the events "prefers dogs" and "female" mutually exclusive?
Choose 1 answer:

problem 5
Find the probability that a randomly selected student prefers dogs or is female.
Enter your answer as a fraction or decimal.
P, left parenthesis, start text, p, r, e, f, e, r, s, space, d, o, g, s, space, o, r, space, i, s, space, f, e, m, a, l, e, end text, right parenthesis, equals
  • Your answer should be
  • an integer, like 6
  • a simplified proper fraction, like 3, slash, 5
  • a simplified improper fraction, like 7, slash, 4
  • a mixed number, like 1, space, 3, slash, 4
  • an exact decimal, like 0, point, 75
  • a multiple of pi, like 12, space, start text, p, i, end text or 2, slash, 3, space, start text, p, i, end text

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