Question

uniform distribution help? PLEASE D:

Answer 1

A.0.60
B.0.80
C.0.10
D.0.40

Answer 2

i dont know how to find the answer

Answer 3

do i subtract?

Answer 4

You wan to find \(P(X<124.2)\). The uniform distribution is defined as
\[f(x)=\begin{cases}
\dfrac{1}{2}&\text{for }123<X<125\\\
0&\text{elsewhere}
\end{cases}\]
The desired probability is given by the integral,
\[P(X<124.2)=\int_{-\infty}^{124.2}f(x)~dx=\frac{1}{2}\int_{123}^{124.2}dx\]
If you're NOT familiar with calculus: this means the same thing as the area under the curve between 123 and 124.2.

Answer 5

wow

Answer 6

i havnt taken calculus yet lol

Answer 7

do i subtract 124.2 from 123?

Answer 8

Okay well if you understand what a probability density function is - which is \(f(x)\) in this case - then it's not too big a step to say that a portion of the area under the distribution represents the proportion or probability of \(X\) falling in some range of values.

Do you agree that the probability under the whole curve is 1? As in, the probability of getting any number between 123 and 125 is 100% ?