8 - ? = -1. the missing number would be 9.
Answer: True
Step-by-step explanation: Because if we have two independent events and want to know the probability of their happening at the same time, we multiply the two probabilities together. "Two events happening at the same time" is a compound event. We more often see this as "P(xy)," the probability of x AND y.
The answer is the third one
Depends is the positive integer is larger than the negative interger for example -10+5=-5.
10+-4=6
9880 different possibilities are there in Sally's new combination option second 9880 is correct.
<h3>What is permutation and combination?</h3>
A permutation is the number of different ways a set can be organized; order matters in permutations, but not in combinations.
We have:
Total unique numbers consists in a Sally locker = 3
From the digits 0 to 39
Total numbers = 40
Apply combination formula:
= C(40, 3)
= 40!/(3!37!)
= 9880
Thus, 9880 different possibilities are there in Sally's new combination option second 9880 is correct.
Learn more about permutation and combination here:
brainly.com/question/2295036
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