Eric wants to estimate the percentage of elementary school children who have social media account. He surveys 450 elementary school children and finds out 280 have a social media account. Identify the values needed to calculate a confidence interval at the 90% confidence level. Then find the confidence interval. P’= Standard deviation p’= =a/2 ( , )

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Ratios

A ratio is a comparison between two numbers of the same kind. It represents how many times one number contains another. It also represents how small or large one number is compared to the other.

Trigonometric Ratios

Trigonometric ratios give values of trigonometric functions. It always deals with triangles that have one angle measuring 90 degrees. These triangles are right-angled. We take the ratio of sides of these triangles.