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:20πmm
Step-by-step explanation:
each pencil diameter=10mm
each pencil diameter=radius Of The band
Radius of band=10mm
Circumference of band=2 x π x radius
Circumference of band=2xπx10
Circumference of band=20π
The length of band is the circumference Of The band
There length of band is 20πmm
Answer: 135 square meters
Mark: 52 meatball sandwiches
Julie: 64 meatball sandwiches
Answer: A is the correct answer