Answer:
0.6804
Step-by-step explanation:
Given that Margie is practicing for an upcoming tennis tournament. Her first serve is good 20 out of 30 times on average. 
Since each trial is independent and there are two outcomes, X no of good serves is binomial with n=6 and p =2/3
Required probability
= Prob that atleast four of 6 times good serve
=
=
Formula used:
P(X=r) =
 
        
                    
             
        
        
        
Answer:
Below.
Step-by-step explanation:
f) (a + b)^3 - 4(a + b)^2   
The (a+ b)^2 can be taken out to give:
= (a + b)^2(a + b - 4) 
= (a + b)(a + b)(a + b - 4).
g)  3x(x - y) - 6(-x + y)
=  3x( x - y) + 6(x - y)
= (3x + 6)(x - y) 
= 3(x + 2)(x - y).
h) (6a - 5b)(c - d) + (3a + 4b)(d - c)
=  (6a - 5b)(c - d) + (-3a - 4b)(c - d)
=  -(c - d)(6a - 5b)(3a + 4b).
i)  -3d(-9a - 2b) + 2c (9a + 2b)
= 3d(9a + 2b) + 2c (9a + 2b)
=  3d(9a + 2b) + 2c (9a + 2b).
= (3d + 2c)(9a + 2b).
j)  a^2b^3(2a + 1) - 6ab^2(-1 - 2a)
=  a^2b^3(2a + 1) + 6ab^2(2a + 1)
= (2a + 1)( a^2b^3 + 6ab^2)
The GCF of a^2b^3 and  6ab^2 is ab^2, so we have:
 (2a + 1)ab^2(ab + 6)
= ab^2(ab + 6)(2a + 1).
 
        
             
        
        
        
Answer:
of the 4 people that have a sister,  2 of them have a brother 
Step-by-step explanation:
 probability of B given A
given that the person has a sister, what is the probability they have a brother
P (B/A) = 1/2 
with this venn diagram
of the 4 people that have a sister,  2 of them have a brother 
 
 
 
        
             
        
        
        
10.75
11.50
11.80
12.55
13.30
14.05
14.80
15.55
        
             
        
        
        
Answer:To find a scale factor between two similar figures, find two corresponding sides and write the ratio of the two sides. If you begin with the smaller figure, your scale factor will be less than one. If you begin with the larger figure, your scale factor will be greater than one.
Step-by-step explanation : )