Answer:
I dont know
Step-by-step explanation:
lx-1 l ≤ 13
There are 2 solutions:
x-1 ≤ 13
and
x-1 ≥ -13
Solve each one
x-1 ≤ 13
add 1 to both sides of the equation
x-1+1≤ 13+1
x ≤ 14
x-1 ≥ -13
Add 1 to both sides:
x-1+1 ≥-13+1
x ≥ -12
-12 ≤ x ≤ 14
ANSWER
0.756
EXPLANATION
Let x represent number of correct answers.
We can find
which leads us to
which uses the compliment of 
to find the probability of getting at least 2 questions correct.
Note that since 
and 
are mutually exclusive, we have
Then 
as we have 
to answer the questions incorrectly divided by the total 
to answer the questions.
Exactly 1 answer correct: 
Therefore
![\begin{aligned} P(x \ge 2) &= 1 - P(x = 0\text{ or }x =1) \\ &=1 - \big[P(x=0) + P(x=1)\big] \\ &=1 - \left[ (3/4)^{10} + {}_{10}C_1 \cdot (3/4)^9(1/4)^1 \right] \\ &\approx 0.756 \end{aligned}](https://tex.z-dn.net/?f=%5Cbegin%7Baligned%7D%0AP%28x%20%5Cge%202%29%20%26%3D%201%20-%20P%28x%20%3D%200%5Ctext%7B%20or%20%7Dx%20%3D1%29%20%5C%5C%0A%26%3D1%20-%20%5Cbig%5BP%28x%3D0%29%20%2B%20P%28x%3D1%29%5Cbig%5D%20%5C%5C%0A%26%3D1%20-%20%5Cleft%5B%20%283%2F4%29%5E%7B10%7D%20%2B%20%7B%7D_%7B10%7DC_1%20%5Ccdot%20%283%2F4%29%5E9%281%2F4%29%5E1%20%5Cright%5D%20%5C%5C%0A%26%5Capprox%200.756%0A%5Cend%7Baligned%7D%20)
Answer:
The probability of picking a purple marble, and then, not replacing picking an orange marble is approximately 20%
Step-by-step explanation:
First we know that there are 20 marbles in the bag, so the probability of picking a purple marble is 11/20. If we take a purple marble out, there will only be 19 marbles remaining in the bag. So the probability of picking an orange marble would be 7/19. Now, all we need to do is multiply the 2 fractions, and we will get 77/380 which equals to which is approximately 20% .
Answer:
72
Step-by-step explanation:
