PLEASE HELP!! Suppose a uniform random variable can be used to describe the outcome of an experiment with outcomes ranging from 40 to 90. What is the mean outcome of this experiment?

How many glue sticks are in a basket containing 96 scissors, if the ratio of glue sticks to scissors is 19 to 57.

Damon makes 20 cups of lemonade by mixing lemon juice and water. the ratio of lemon juice to water is shown in the tape diagram. lemon juice\text{lemon juice} lemon juice water\text{water} water how much lemon juice did damon use in the lemonade? cups

Use sigma notation to represent the following series for 9 terms.