ISEE Lower Level Quantitative : How to find the probability of an outcome

Example Questions

Example Question #31 : Data Analysis And Probability

In a washing machine, there are  blankets,  shirts, and  pants. What is the probability of taking out a peice of clothing first?

Explanation:

Probability can be expressed as a fraction. The numerator represents the total number of what is being chosen and the denominator represents the total number of items that can be chosen. In this problem, there are  pieces of clothing and a total of  items in the washing machine. This is represented as the fraction: . This can be reduced to . The answer is .

Example Question #31 : Probability

A bag contains differently colored balls. In it are  pink balls,  red balls, and  green balls. What is the probability of choosing a red ball at random?

Explanation:

Probability can be expressed as a fraction. The numerator represents the total number of what is being chosen and the denominator represents the total number of items that can be chosen. In this problem, there are  red balls and a total of  balls in the bag. This is represented as the fraction: . This can be reduced to . The answer is .

Example Question #31 : Probability

A bag contains differently colored balls. In it are  pink balls,  red balls, and  green balls. What is the probability of choosing a pink ball at random?

Explanation:

Probability can be expressed as a fraction. The numerator represents the total number of what is being chosen and the denominator represents the total number of items that can be chosen. In this problem, there are  red balls and a total of  balls in the bag. This is represented as the fraction: . This can be reduced to . The answer is .

Example Question #31 : How To Find The Probability Of An Outcome

A game requires you to throw a ball at some randomly-arranged colored tiles in order to win a prize. There are  white tiles,  blue tiles,  red tiles, and  black tiles. What is the probability of hitting a black tile?

Explanation:

Probability can be expressed as a fraction. The numerator represents the total number of what is being chosen and the denominator represents the total number of items that can be chosen. In this problem, there are  black tiles and a total of  tiles. This is represented as the fraction: . This can be reduced to . The answer is .

Example Question #32 : Data Analysis And Probability

Misha is choosing movies from a bin at a store. In the bin are  action movies,  comedies,  documentaries, and  other types of films. If she chooses randomly, what is the probability that Misha will pick out a comedy movie?

Explanation:

Probability can be expressed as a fraction. The numerator represents the total number of what is being chosen and the denominator represents the total number of items that can be chosen. In this problem, there are  comedy movies and a total of  movies. This is represented as the fraction: . This can be reduced to . The answer is .

Example Question #32 : How To Find The Probability Of An Outcome

Jessica has a box of chocolates.  have buttercream filling,  have cherry filling,  have raspberry filling,  have coconut filling, and  have no filling. What is the probability of Jessica choosing a chocolate with no filling?

Explanation:

Probability can be expressed as a fraction. The numerator represents the total number of what is being chosen and the denominator represents the total number of items that can be chosen. In this problem, there are  chocolates with no filling and a total of  chocolates. This is represented as the fraction: . This can be reduced to . The answer is .

Example Question #34 : Outcomes

A group of kids are playing duck-duck-goose. In the circle sit  third graders,  fourth graders, and  fifth graders. What is the probability that a third or fourth grader will be chosen?

Explanation:

Probability can be expressed as a fraction. The numerator represents the total number of what is being chosen and the denominator represents the total number of items that can be chosen. In this problem, there are  third and fourth graders and a total of  students. This is represented as the fraction: . This can be reduced to . The answer is  .

Example Question #33 : Data Analysis And Probability

A jar contains  candy bars,  lollipops, and  other types of sweets. What is the probability of drawing a lollipop at random from the jar?

Explanation:

Probability can be expressed as a fraction. The numerator represents the total number of what is being chosen and the denominator represents the total number of items that can be chosen. In this problem, there are  lollipops and a total of  pieces of candy. This is represented as the fraction: . This can be reduced to . The answer is .

Example Question #32 : Probability

Jacob has  mechanical pencils,  colored pencils, and  erasers in his bag. What is the probability of him taking out a colored pencil at random from the bag?

Explanation:

Probability can be expressed as a fraction. The numerator represents the total number of what is being chosen and the denominator represents the total number of items that can be chosen. In this problem, there are  colored pencils and a total of  items. This is represented as the fraction: . This can be reduced to . The answer is .

Example Question #33 : Probability

If Justin rolls a six-sided die, what is the probability of it landing on an even number?