Mrs. Baker’s students write word problems each week, and she selects one student's word problem to display on a bulletin board each week. Each student's name is placed in a bag from which Mrs. Baker draws a name. What is the probability that an eighth grade student will NOT be selected?
EXPLAIN your process and give your answer as a % or simplified fraction.
To calculate the probability that an eighth grade student will NOT be selected, we first need to determine the total number of students in the class and the total number of eighth grade students specifically.
Let's say there are 30 students in Mrs. Baker's class, and 10 of them are eighth graders.
The probability of selecting an eighth grade student can be calculated as:
Number of ways to select an eighth grade student / Total number of students
= 10 (number of eighth graders) / 30 (total number of students)
= 1/3
Since the probability of selecting an eighth grade student is 1/3, the probability of NOT selecting an eighth grade student would be the complement of that, which is 1 - 1/3 = 2/3.
Therefore, the probability that an eighth grade student will NOT be selected is 2/3 or approximately 66.67%.
Can you rewrite it like a 7th grader?
Sure! So, in Mrs. Baker's class, she has 30 students. Out of those 30 students, 10 of them are in the eighth grade. When Mrs. Baker picks a student's name from a bag to display their word problem, the chance of her picking an eighth grader is 1 out of 3, because there are 10 eighth graders out of 30 students.
Since we want to know the chance of NOT picking an eighth grader, we take the chance of picking an eighth grader (1/3) and subtract it from 1. This gives us the chance of NOT picking an eighth grader, which is 2 out of 3 or about 67%. So, the probability that an eighth grade student will NOT be selected is 2/3 or about 67%.