The Editor-in-Chief of the student newspaper was doing a final review of the articles submitted for the upcoming edition. Of the 7 total articles submitted, 5 were editorials. If she liked all the articles equally, and randomly selected 4 articles to go on the front cover, what is the probability that all of them are editorials? Write your answer as a decimal rounded to four decimal places. ____
Q. The Editor-in-Chief of the student newspaper was doing a final review of the articles submitted for the upcoming edition. Of the 7 total articles submitted, 5 were editorials. If she liked all the articles equally, and randomly selected 4 articles to go on the front cover, what is the probability that all of them are editorials? Write your answer as a decimal rounded to four decimal places. ____
Calculate Total Number of Ways: First, calculate the total number of ways to choose 4 articles out of 7. This is a combination problem, so we use the formula for combinations: C(n,k)=k!(n−k)!n!. Calculate C(7,4) for the total number of ways to choose 4 articles. C(7,4)=4!(7−4)!7!=(4!⋅3⋅2⋅1)(7⋅6⋅5⋅4!)=(3⋅2⋅1)(7⋅6⋅5)=35.
Calculate Ways to Choose Editorials: Next, calculate the number of ways to choose 4 editorials out of the 5 available.Use the combination formula again: C(5,4).C(5,4)=(4!(5−4)!)5!=(4!⋅1!)(5⋅4!)=15=5.
Find Probability: Now, find the probability by dividing the number of ways to choose 4 editorials by the total number of ways to choose 4 articles.Probability = Number of ways to choose 4 editorials / Total number of ways to choose 4 articles.Probability = 355.
Convert to Decimal: Simplify the fraction355 to get the decimal form.355=71. Convert 71 to a decimal and round to four decimal places.71≈0.1429.
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