Stacked notation (fractions, radicals, matrices) does not survive text extraction. The image above is the question as printed; the text below it is approximate. Open the original booklet →
The whole numbers 1 through 30 were each written on separate pieces of paper. Those 30 pieces of paper were put into a jar. One piece of paper will be randomly drawn from this jar. What is the probability that this piece of paper will have a prime number written on it? _ 1
Correct answer: J
Explanation from ACT Education Corp.
This question also appears in ACT QuizMe official practice questions, which explains every answer choice.
A. Incorrect. Remember that the probability of choosing a paper with a prime number on it is the total possible number of papers with prime numbers divided by the total number of papers in the jar. You may have divided the number of papers being chosen, 1, by the total number of papers in the jar, 30.
B. Incorrect. Remember that the probability of choosing a paper with a prime number on it is the total possible number of papers with prime numbers divided by the total number of papers in the jar. You may have divided the number of papers being chosen, 1, by the total number of papers in the jar without prime numbers on them, 20.
C. Incorrect. Remember that the probability of choosing a paper with a prime number on it is the total possible number of papers with prime numbers divided by the total number of papers in the jar. You may have divided the number of papers being chosen, 1, by the total number of papers in the jar with prime numbers on them, 10.
D. Correct. There are 10 prime numbers between 1 and 30: 2, 3, 5, 7, 11, 13, 17, 19, 23, and 29. The probability of choosing a paper with a prime number on it is the total possible number of papers with prime numbers divided by the total number of papers in the jar, 10 over 30.
Loading…
Searched on YouTube by reporting category, not by question text. Open this search on YouTube →
Extracted from a print-layout PDF: equations, figures and charts do not survive as text. Use the original PDF for anything that renders poorly. ACT® is a registered trademark of ACT Education Corp., which is not affiliated with, does not sponsor, and does not endorse this project.