PLEASE HELP ASAP! Several books are placed on the bottom three shelves of a bookcase. When 1 book was taken from the first shelf, 2 books were taken from the second shelf, 3 books were taken from the third shelf, and all these books were placed on the top fourth shelf, the quantity of books on all the shelves became equal. How many books are in the bookcase?

24 books

Step-by-step explanation:

Initially the top shelf has no books placed on

Then books added to this:

And now all 4 shelves have same amount of books. So total number is:

There are 24 books in the bookcase

d. 24+-0.114

step-by-step explanation:

the question requires us to calculate the approximate 95% confidence interval for the mean number of ounces of ketchup per bottle in the sample given the following statistics;

sample mean = 24

standard deviation, σ = 0.4

sample size , n = 49

the confidence interval for a population mean is calculated using the formula;

sample mean ± z-score*(σ/sqrt(n))

the z-score associated with a 95% confidence interval, from the standard normal tables, is;

1.96

substituting these values into the formula;

24 ± 1.96*(0.4/7)

= 24 ± 0.112

from the alternatives given, choice d is closest to the above expression;

this excerpt is taken from the book “we shall not be moved : the women’s factory strike of 1909 “ and is written by joan dash. it is the story of the great strike when almost 30thousand women working in factories in america formed a union to fight unsafe working conditions, long working hours and miserable wages.

question: which best states the author’s purpose for including this information in the text?

answer: to challenge the reader’s ideas about a historical event