a. Let
be a random variable representing the weight of a ball bearing selected at random. We're told that
, so

where
. This probability is approximately

b. Let
be a random variable representing the weight of the
-th ball that is selected, and let
be the mean of these 4 weights,

The sum of normally distributed random variables is a random variable that also follows a normal distribution,

so that

Then

c. Same as (b).
Answer:
4.25
Step-by-step explanation:
5-3/4=4.25
sry if im wrong hope this helps
brainliest? please?
I solved 2/5(x − 2) = 4x. I don't know why you included those extra numbers.
<u>-2/9</u>
Answer:
the most she can drive is 162 miles
Step-by-step explanation:
-2 -13.8x = -8 -6x -1
First, I distributed the negative 1 that was outside of the parentheses to the positive 6x and the positive 1.
-2 -13.8x = -9 -6x
Then I added the negative 8 to the negative 1 which equals negative 9.
-2 -13.8x +6x = -9 -6x +6x
After that I used the addition property and added a positive 6x to both sides.
-2 -7.8x = -9
Then simplifying.
+2 -2 -7.8x = -9 +2
After simplifying, I used the addition property again, adding a positive 2 to both sides.
-7.8x = -7
Simplified.
-7.8x (-1) = -7 (-1)
Then I multiplied both sides by with a negative 1 since the variable cannot be a negative.
7.8x = 7
Simplified
(1/7.8) 7.8x = (1/7.8) 7
Then, to isolate the veriable, I multiplied 1/7.8 to both sides.
x = 1.11428571429
The answer !
I hope this helped !