Answer: D) 9.4
Step-by-step explanation:
ANSWER
![P(not \: B) = \frac{1}{4}](https://tex.z-dn.net/?f=P%28not%20%5C%3A%20B%29%20%3D%20%20%5Cfrac%7B1%7D%7B4%7D%20)
EXPLANATION
If A and B are independent events, then
P(A and B)=P(A)×P(B)
![\frac{3}{10} = \frac{2}{5} \times \: P(B)](https://tex.z-dn.net/?f=%20%5Cfrac%7B3%7D%7B10%7D%20%20%3D%20%20%5Cfrac%7B2%7D%7B5%7D%20%20%5Ctimes%20%20%5C%3A%20P%28B%29)
Multiply both sides by;
![\frac{5}{2}](https://tex.z-dn.net/?f=%20%5Cfrac%7B5%7D%7B2%7D%20)
![\frac{5}{2} \times \frac{3}{10} = \frac{5}{2} \times \frac{2}{5} \times \: P(B)](https://tex.z-dn.net/?f=%20%5Cfrac%7B5%7D%7B2%7D%20%20%5Ctimes%20%20%5Cfrac%7B3%7D%7B10%7D%20%20%3D%20%20%20%5Cfrac%7B5%7D%7B2%7D%20%20%5Ctimes%20%5Cfrac%7B2%7D%7B5%7D%20%20%5Ctimes%20%20%5C%3A%20P%28B%29)
![\frac{3}{4} =P(B)](https://tex.z-dn.net/?f=%20%5Cfrac%7B3%7D%7B4%7D%20%20%3DP%28B%29)
![P(not \: B) = 1 - P(B)](https://tex.z-dn.net/?f=P%28not%20%5C%3A%20B%29%20%3D%201%20-%20P%28B%29)
![P(not \: B) = 1 - \frac{3}{4}](https://tex.z-dn.net/?f=P%28not%20%5C%3A%20B%29%20%3D%201%20-%20%5Cfrac%7B3%7D%7B4%7D%20)
![P(not \: B) = \frac{1}{4}](https://tex.z-dn.net/?f=P%28not%20%5C%3A%20B%29%20%3D%20%20%5Cfrac%7B1%7D%7B4%7D%20)
Total students = 4 * 21 = 84
Answer:
2x-3+x+x+3=36
Step-by-step explanation:
since perimeter is all the sides added together and the total perimeter is 36.
Answer: angle 2 is 28
Step-by-step explanation:if angle (1) and (2) are supplementary which equals 180degrees; we know angle one is 152 degrees, so a simple 180-152= 28 degrees; so angle 2 is 28