Two dice are thrown simultaneously. What is the probability of rolling a total sum of 7?
Answer and explanation
Correct answer: C. 1/6
- Step 1: Total possible outcomes for two dice = 6 6 = 36 outcomes. Step 2. Outcomes summing to 7 are (1,6), (2,5), (3,4), (4,3), (5,2), (6,1): exactly 6 outcomes. Probability = 6/36 = 1/6. Answer: 1/6. Why not the others:* 1/12 is 3/36; 5/36 is the probability of sum = 6 or 8; 7/36 divides 7 by 36.
Practise more Statistics, Probability and Everyday Arithmetic.
Free questions with an explanation for every one, and full timed Basic Education Certificate Examination mock tests.
More Statistics, Probability and Everyday Arithmetic questions
- The marks obtained by seven pupils in a science test are: 12, 15, 18, 14, 16, 15, and 15. What is the mode?
- Find the median of the following set of numbers: 8, 12, 5, 15, 22, 9, 17.
- Calculate the arithmetic mean of the scores: 6, 8, 11, 14, and 16.
- The mean of four numbers is 18. If three of the numbers are 14, 16, and 22, find the fourth number.
- What is the range of the test scores: 24, 38, 19, 45, 52, 31, and 28?
- A fair six-sided die is rolled once. What is the probability of obtaining a prime number?