Melissa rolls two number cubes, each with sides that are labeled 1 to 6. What is the probability that the product of the numbers will be greater than or equal to 18? Write your answer in probability notation as a simplified fraction.
3 answers
please help me!
how many pairs of numbers produce a product of at least 18?
36, 45 46, 54 55 56, 63 64 65 66 for a total of 10
So, P(ab >= 18) = 10/36
36, 45 46, 54 55 56, 63 64 65 66 for a total of 10
So, P(ab >= 18) = 10/36
Possible products ≥ 18
18 = 3*6 or 6*3
19 : none
20: 4*5 or 5*4
21, 22, 23 : all none
24 : 6*4 or 4*6
25 : 5*5
26-29: none
30: 5*6 or 6*5
36 : 6*6
prob of each product is the same,
so
so the only products are 18, 20, 24, 25, 30, 36
prob( product of 2 numbers to be 18,20,24, or 30) = 8(1/36)
prob(25 or 36) = 2(1/36) = 1/18
prob(your event) = 8/36 + 1/18 = 5/18
You could construct a matrix of 6 rows and 6 columns, where each entry
would be the product of the row and column numbers.
counting all the products ≥ 18 would be 10
prob(your event) = 10/36 = 5/18
Don't know where one can get dice to have products of the numbers showing to be greater than 36.
18 = 3*6 or 6*3
19 : none
20: 4*5 or 5*4
21, 22, 23 : all none
24 : 6*4 or 4*6
25 : 5*5
26-29: none
30: 5*6 or 6*5
36 : 6*6
prob of each product is the same,
so
so the only products are 18, 20, 24, 25, 30, 36
prob( product of 2 numbers to be 18,20,24, or 30) = 8(1/36)
prob(25 or 36) = 2(1/36) = 1/18
prob(your event) = 8/36 + 1/18 = 5/18
You could construct a matrix of 6 rows and 6 columns, where each entry
would be the product of the row and column numbers.
counting all the products ≥ 18 would be 10
prob(your event) = 10/36 = 5/18
Don't know where one can get dice to have products of the numbers showing to be greater than 36.