Answer:
a) 
b) 
Step-by-step explanation:
Number of balls in the urn = 12
Number of white balls in the urn = 4
So, number of balls which are not white = 12 - 4 = 8
We know that probability = No. of outcomes/Total number of outcomes
Let
denotes the event of getting white ball by A, B and C
a) each ball is replaced after being drawn.
Probability = Number of white balls/Total number of balls
Solution: 
b)the balls that are withdrawn are not replaced.
Solution:
If A wins: 
If A lost and B wins: 
If A and B lost and C wins: 
and so on....
Answer:
30.25 & 33.25
Step-by-step explanation:
x² + 11x + (5.5)² = 3+ (5.5)²
x² + 11x + 30.25 = 33.25
Answer:
7.5
Step-by-step explanation:
5/6=x/9
cross multiply
6x=45
x=45/6
x=7 3/6 = 7 1/2 = 7.5
Answer:
n = ±6 .
Step-by-step explanation:
A quadratic equation is given to us and we need to find out the solution of the given equation . The given equation is ,
Subtracting 18 both sides ,
Multiplying both sides by -2 ,
On simplyfing , we get ,
Putting squareroot both sides ,
This equals to ,
<u>Hence</u><u> the</u><u> </u><u>value</u><u> of</u><u> </u><u>n </u><u>is </u><u>±</u><u>6</u><u> </u><u>.</u>