Answer:

Step-by-step explanation:
Given



Required
The probability of selecting 2 same colors when the first is not replaced
The total number of ball is:


This is calculated as:

So, we have:

<em>Note that: 1 is subtracted because it is a probability without replacement</em>






Answer:
ok
Step-by-step explanation:
Answer:
129/200
Step-by-step explanation:
Answer:
at least 20 rows.
Step-by-step explanation:
when you add the students, teachers, and chaperones, it comes to 159. then you divide 159 by the number of seats each row has, so 159/8 = 19.875, you would have to round to the nearest whole number so 20 should be correct.