A test has a mean grade of 75 with standard deviation of 5. The distribution of test grades is normal. What percent of the test grades are below 60? Joe wants to find a 90% confidence interval for his mean running time for his usual route. He has sample data for 30 days of running. The mean time for the 30 days is 22 minutes with standard deviation of 2 minutes. What is the 90% confidence interval of his overall mean running time?

What is the margin of error for a 98% confidence interval if we have a sample mean of 50, sample standard deviation of 6, and a sample size of 100?

Find the boundaries of the middle 70% of the data in a normal distribution that has a mean of 40 and standard deviation of 4.

What proportion of the prices of a pair of sneakers are above $150 if the mean price is $95 and the standard deviation is $15. Assume the prices are nor

40 x 50 = 2000

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.

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.