Heather buys a bag of cookies that contains 5 chocolate chip cookies, 8 peanut butter cookies, 9 sugar cookies and 4 oatmeal cookies. What is the probability that Heather reaches in the bag and randomly selects 2 peanut butter cookies from the bag? Round your answer to four decimal places.

0.0862 = 8.62% probability that Heather reaches in the bag and randomly selects 2 peanut butter cookies from the bag

Step-by-step explanation:

A probability is the number of desired outcomes divided by the number of total outcoes.

The order in which the cookies are selected is not important, so we use the combinations formula to solve this question.

Combinations formula:

is the number of different combinations of x objects from a set of n elements, given by the following formula.

Desired outcomes:

2 peanut butter cookies, from a set of 4. So

Total outcomes:

2 cookies from a set of 5+8+9+4 = 26. So

Probability:

0.0862 = 8.62% probability that Heather reaches in the bag and randomly selects 2 peanut butter cookies from the bag

ratios represent a pattern or relationship that can be scaled.

equivalent ratios are pairs of ratios that represent the same relationship between quantities, and can be generated by multiplying or dividing both quantities in the ratio by the same factor.

in this lesson, students will use double number lines and ratio reasoning to solve ratio problems. by partitioning double number lines into proportionate intervals, students will build an understanding of equivalent ratio relationships as those that are generated by multiplying or dividing two related quantities by the same number. this lesson will build upon students' prior understanding of multiplicative comparisons, number line reasoning and equivalent fractions (while highlighting the difference between equivalent fractions and equivalent ratios); and will build toward future work in this unit on building ratio tables, and work in future grades in proportionality, scaling, and expressing and graphing linear functions.

step-by-step explanation:

ratios represent a pattern or relationship that can be scaled.

equivalent ratios are pairs of ratios that represent the same relationship between quantities, and can be generated by multiplying or dividing both quantities in the ratio by the same factor.

in this lesson, students will use double number lines and ratio reasoning to solve ratio problems. by partitioning double number lines into proportionate intervals, students will build an understanding of equivalent ratio relationships as those that are generated by multiplying or dividing two related quantities by the same number. this lesson will build upon students' prior understanding of multiplicative comparisons, number line reasoning and equivalent fractions (while highlighting the difference between equivalent fractions and equivalent ratios); and will build toward future work in this unit on building ratio tables, and work in future grades in proportionality, scaling, and expressing and graphing linear functions.

answer: what are the answer choices?

step-by-step explanation: