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You roll a die 5 times. What is the probability that:

a. The number 1 is rolled each time?
b. An odd number is rolled each time?

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Thomas L. | Mathematics TutorMathematics Tutor
4.9 4.9 (26 lesson ratings) (26)
a. consecutive rolls mean multiplication of each individual probability.  there is 1 one on a die, and 6 total outcomes which means a 1/6 probability each time(no need to subtract 1, you can't take the #1 off of a die.)
next multiply 1/6 times 1/6 times 1/6 times....a total of 5 times.
b. how many odd numbers are there on a die?  1,2,3,4,5,6 possibilities, so 1,3,5 are odd.  3/6 probability.
consecutive rolls mean multiplication.  3/6 times 3/6 times.... a total of 5 times.  reduce you answer.
Kirill Z. | Physics, math tutor with great knowledge and teaching skillsPhysics, math tutor with great knowledge...
4.9 4.9 (174 lesson ratings) (174)
a. (1/6)6, since every roll does not depend on the previous outcome, and the probability of rolling 1 once is 1/6.
b. You can roll odd number by 3 ways: roll 1, 3, or 5. So the probability to roll odd number once is 1/2, then rolling it 6 times is (1/2)6=1/64=0.015625.