g Four distinct numbers are to be selected from the list {−5, −4, −3, −2, −1, 1, 2, 3, 4}. In how many ways can this selection be done so that the product of the four numbers is positive?

66 possible combinations.

Step-by-step explanation:

To have a positive product we have 3 situations.

The 4 numbers are positive:

if the "order" of the selection does not matter, then we have only one solution here:

1, 2, 3 and 4.

Second case, we have two negative numbers and two positive numbers.

Here we can use the fact that in a group of N objects, the number of different combinations of K objects (where K ≤ N) is:

Here we have 5 negative numbers and we want to make groups of 2, so the possible combinations are:

And we have exactly the same for the other two positive numbers, but in this case we have N = 4 and  K = 2.

The total number of combinations is the product of those two:

C = 10*6 = 60 combinations

Now, the last option is that the 4 numbers are negative numbers, so here we have 5 negative numbers and we want to make groups of 4.

So in total, we have: 1 + 60 + 6 = 66 possible combinations.

20

step-by-step explanation:

answer: a. 13/44

step-by-step explanation: judging by the information given to us, we are looking for experimental probability. we can see that 13 males have chosen chocolate ice cream. there are 44 ice creams in total (remember that the total is always the denominator). so our answer is 13/44.