With help of permutations and combinations we can calculate the probability of some event to happen,if the event is composed from several other events (when is a list)
If the order of the events doesn't matter then we have a combination, if the order do matter then we have a permutation. We can say that a permutation is an ordered combination.
The number of permutations of n objects taken r at a time is determined by the following formula:P(n,r)=n!(n-r)!
<span>The number of combinations of n objects taken r at a time is determined by the following formula: C(n,r)=n!/(n-r)!r!</span>
Answer:
16 students got an A
Step-by-step explanation:
Set up an equation to compare the ratio to the scores:
Cross multiply:
80 = 5x
Divide each side by 5:
x = 16
Now, check if
16/8 = 2
40/8 = 5
The ratios are the same! Therefore, 16 students got an A!
Hope this helps! Feel free to contact me if you have any questions :)
Answer:
Answer = <u>57</u>
Step-by-step explanation:
Two prime numbers
whose sum is 61 = 59 , 2
= 59 + 2
= 61
Diffrence = 59 - 2
= <u>57</u>.
Hope it helps.
Answer:
19
Step-by-step explanation:
8*4=32
Then
32-13=19
So answer is 19.