The image is kinda blurry, but from what I can gather, the notation in the attachment means
![p_X[x_k]\equiv\mathbb P(X=k)=\begin{cases}(1-p)^{k-1}p&\text{for }k=1,2,\ldots\\0&\text{otherwise}\end{cases}](https://tex.z-dn.net/?f=p_X%5Bx_k%5D%5Cequiv%5Cmathbb%20P%28X%3Dk%29%3D%5Cbegin%7Bcases%7D%281-p%29%5E%7Bk-1%7Dp%26%5Ctext%7Bfor%20%7Dk%3D1%2C2%2C%5Cldots%5C%5C0%26%5Ctext%7Botherwise%7D%5Cend%7Bcases%7D)
Then
a)
![p_X[x_k\le4]\equiv\mathbb P(X\le4)=\mathbb P(X=1)+\mathbb P(X=2)+\mathbb P(X=3)+\mathbb P(X=4)](https://tex.z-dn.net/?f=p_X%5Bx_k%5Cle4%5D%5Cequiv%5Cmathbb%20P%28X%5Cle4%29%3D%5Cmathbb%20P%28X%3D1%29%2B%5Cmathbb%20P%28X%3D2%29%2B%5Cmathbb%20P%28X%3D3%29%2B%5Cmathbb%20P%28X%3D4%29)
b)

c)
Answer:
<h2>i solve mo para ka namang walang utak</h2>
Step-by-step explanation:
<h2>shhhhhhhhh</h2>
Using the given equation, set H to 8 meters and solve for t:
8 = 3 + 20t -5t^2
Subtract 8 from each side:
3 + 20t -5t^2 -8 = 0
Simplify:
20t - 5t^2-5 =0
Factor out -5:
-5(t^2-4t+1)=0
Divide both sides by -5:
t^2 - 4t +1 = 0
Using the quadratic formula solve for t:
t = 2 +/- √3
t = 3.73 or 0.27
Answer: Le preguntaste a tu maestro?
Step-by-step explanation:
Answer: it’s 20
We have, 120% × x = 24
or,
120/100 × x = 24
Multiplying both sides by 100 and dividing both sides by 120,
we have x = 24 × 100/120
x = 20
If you are using a calculator, simply enter 24×100÷120, which will give you the answer.