Answer:
701 revolutions
Step-by-step explanation:
Given: Length= 2.5 m
Radius= 1.5 m
Area covered by roller= 16500 m²
Now, finding the Lateral surface area of cylinder to know area covered by roller in one revolution of cylindrical roller.
Remember; Lateral surface area of an object is the measurement of the area of all sides excluding area of base and its top.
Formula; Lateral surface area of cylinder= 
Considering, π= 3.14
⇒ lateral surface area of cylinder= 
⇒ lateral surface area of cylinder= 
∴ Area covered by cylindrical roller in one revolution is 23.55 m²
Next finding total number of revolution to cover 16500 m² area.
Total number of revolution= 
Hence, Cyindrical roller make 701 revolution to cover 16500 m² area.
Answer:
62.17% probability that a randomly selected exam will require more than 15 minutes to grade
Step-by-step explanation:
Problems of normally distributed samples are solved using the z-score formula.
In a set with mean
and standard deviation
, the zscore of a measure X is given by:

The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the pvalue, we get the probability that the value of the measure is greater than X.
In this problem, we have that:

What is the probability that a randomly selected exam will require more than 15 minutes to grade
This is 1 subtracted by the pvalue of Z when X = 15. So



has a pvalue of 0.3783.
1 - 0.3783 = 0.6217
62.17% probability that a randomly selected exam will require more than 15 minutes to grade
One is a, and the other is just A.
Please give brainliest. Thanks!
Answer:
B
Step-by-step explanation: