Since <em>X</em> follows a binomial distribution, its mean and variance are
<em>np</em> = 3
<em>np</em> (1 - <em>p</em>) = 2
Substitute <em>np</em> = 3 in to the second equation to solve for <em>p</em> :
3 (1 - <em>p</em>) = 2
1 - <em>p</em> = 2/3
<em>p</em> = 1/3
Solve for <em>n</em> :
<em>n</em> (1/3) = 3
<em>n</em> = 9
Answer:
0.7 kg = $1
Step-by-step explanation:
7 kg - $10
? kg - $1
7 / 10 = 0.7
0.7 kg = $1
Let me know if I did something wrong :)
Answer:
48 students in the class
Step-by-step explanation:
The ratio of girls to boys is 3 : 5 = 3x : 5x ( x is a multiplier ) , then
5x = 3x + 12 ( 12 more boys than girls )
Subtract 3x from both sides )
2x = 12 ( divide both sides by 2 )
x = 6
Then
number of girls = 3x = 3 × 6 = 18
number of boys = 5x = 5 × 6 = 30
total students in class = 18 + 30 = 48
Answer:
7x+Y=-2
Step-by-step explanation:
(y-y1)=m(x-x1)
(Y+4)=-7(x-2)
Y+4=-7x+2
Y+7x=2-4
7x+Y=-2
