Answer:
66
Step-by-step explanation:
If there are <em>n</em> students, then the number of pairs is 
.
With 12 students, 
pairs can be formed.
The reason the formula works is this: Each of the 12 students can be paired with 11 other students (no student is paired with him/her self). But counting 12 x 11 = 132 counts each pair <u>twice</u>. Example: student A can be paired with student B,..., student B can be paired with student A. The pair was counted two times.
See the attached image that shows pairings of 5 students. There are
5(5 - 1)/2 = 5(4)/2 = 10 pairs.
Since the dice are fair and the rolling are independent, each single outcome has probability 1/15. Every time we choose
We have 
and 
, because the dice are fair.
Now we use the assumption of independence to claim that
Now, we simply have to count in how many ways we can obtain every possible outcome for the sum. Consider the attached table: we can see that we can obtain:
- 2 in a unique way (1+1)
- 3 in two possible ways (1+2, 2+1)
- 4 in three possible ways
- 5 in three possible ways
- 6 in three possible ways
- 7 in two possible ways
- 8 in a unique way
This implies that the probabilities of the outcomes of 
are the number of possible ways divided by 15: we can obtain 2 and 8 with probability 1/15, 3 and 7 with probability 2/15, and 4, 5 and 6 with probabilities 3/15=1/5
Answer:
40 Minutes.
Step-by-step explanation:
The current time = 4:12 p.M.
Emma's mom will be home from work in 70 minutes.
70 minutes = 1 hour 10 Minutes= 1: 10 Hours
Therefore, Emma's Mom will get home by 5: 22 p.m.
Emma has gymnastics lessons at 6 : 00 p.M.
To determine how much time Emma will have between the time that her mom gets home from work and the beginning of gymnastics lessons, we simply subtract 5:22 from 6.
Emma will have 40 Minutes.
<span>There is no number that both 55 and 122 are divisible by. ....so 55/122 is the simplified form itself ....if u divide u will get the answer in decimals ....
Hope it helps !!!
</span>
It is a astronomer ..please mark brainliest
