Using the concept of probability and the arrangements formula, there is a
0.002 = 0.2% probability that the first 8 people in line are teachers.
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- A probability is the <u>number of desired outcomes divided by the number of total outcomes.</u>
- The order in which they are positioned is important, and all people will be positioned, and thus, the arrangements formula is used to find the number of outcomes.
The number of possible arrangements from a set of n elements is given by:

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The desired outcomes are:
- First 8 people are teachers, in <u>8! possible ways.</u>
- Last 4 are students, in <u>4! possible ways.</u>
Thus, 
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For the total outcomes, <u>number of arrangements of 12 people</u>, thus:

The probability is:

0.002 = 0.2% probability that the first 8 people in line are teachers.
A similar problem is given at brainly.com/question/24650047
Answer:
1/11
Step-by-step explanation
There are 12 marbles in the bag. When we first pick we have 4 blue marbles. So 4 blue marbles/12 random marbles. When we pick blue and noted, there are 3 marbles in the bag because of we didn't put it back. So when we choose again there are 11 marbles and 3 blue marbles in the bag. Choosing a blue one case is 3/11.
The last part of this case is happening as a chain. So we need to multiply our two answers.
=4/12*3/11
=1/3*3/11
=1/11
Answer:
$199.50
Step-by-step explanation:
10% discount of $34 = 10/100*34 = $3.40
so, a single shirt costs $34-$3.40 = $30.60
half off = 50% discount of $31 = 50/100*31 = $15.50
so, a single cap costs $31-$15.50 = $15.50
so, 5 shirts and 3 caps cost now
5*$30.60 + 3*$15.50 = $153 + $46.50 = $199.50
but careful - can this be a trick question ?
the phrasing of the problem description can also suggest that the discounts are only listed to confuse us and are already included in the mentioned prices ("worth" $34 - what does that mean ? because including the discounts they are currently "worth" their prices).
then it would just plainly be
5*$34 + 3*$31 = $170 + $93 = $263
The answer would be -12+8i