so on the last post i couldn't reply cause it was locked, but i already answered them on my own. i don't know how to delete the questions sorry about that, and i wasn't really expecting to gett an answer but courage the cowardly dog helped so i was able to solve the other one's by myself
but for any other person having a hard time answering the questions these were my answers
1. A normal distribution has a mean of 103 and a standard deviation of 2.7.
What is the z-score of 105?
Answer: 0.74
2. A normal distribution has a mean of 103 and a standard deviation of 2.7.
What is the z-score of 105?
Answer: 17.8
3. Use technology or a z-score table to answer the question.
The weights of logs in a wood pile are normally distributed with a mean of 17 pounds and a standard deviation of 3.4 pounds. The wood pile is composed of 325 logs.
How many of the logs will weigh 15 pounds or more
Answer: 235
4. The ages of members of a policy action group are normally distributed with a mean of 33 years and a standard deviation of 2 years.
There are 400 members in the group.
About how many members are expected to be between 29 years old and 37 years old
Answer: 380
5. Use technology or a z-score table to answer the question.
The expression P(z<1.71) represents the area under the standard normal curve below the given value of z.
What is P(z<1.71)?
Answer: 0.9564
6. Use technology or a z-distribution table to find the indicated area.
The weights of tomatoes in a bin are normally distributed with a mean of 120 grams and a standard deviation of 4.3 grams.
Approximately 40% of the tomatoes weigh less than which amount?
Answer: 119 g
7. Suppose the scores on a grammar quiz are normally distributed with a mean of 76 and a standard deviation of 8.
Which group describes 16% of the population of grammar quiz scores?
Answer: scores below 68
8.
Select Yes or No to state whether each data set is likely to be normally distributed.
Data Set
the weights of the babies born at a hospital yes/no
the number of babies born each month at a hospital yes/no
the number of rooms on each floor of a hospital yes/no
the lengths of the babies born at a hospital yes/no
Answer: yes, yes, no, yes
9. The masses of the oranges on sale at a farm stand are normally distributed with a mean of 239 grams and a standard deviation of 25 grams
Answer 0.8
10. The heights of the peach trees in an orchard are normally distributed with a mean of 12.5 feet and a standard deviation of 1.8 feet.
What is the height of a peach tree with a z-score of −0.5−0.5 ?
Answer: 11.6
11. Use technology or a z-distribution table to find the indicated area.
The masses of the eggs collected on a farm are normally distributed with a mean of 55 grams and a standard deviation of 4.2 grams.
Approximately 80% of the eggs on the farm have a mass greater than which mass?
Answer: 51.5 g
12. Use technology or a z-score table to answer the question.
The weights of boxes of rice produced at a factory are normally distributed with a mean of 24 ounces and a standard deviation of 1.3 ounces. Consider a shipment of 1200 boxes of rice.
How many of the boxes will weigh 25 ounces or less?
Answer: 935
btw wont post the other 50 questions on the study guide , any onlookers just look at pavlov's formula and the way he/she answered it
