To find a baseball pitcher's earned run average (era), you can use the formula ei = 9r, in which e represents era, i represents the number of innings pitched, and r represents the number of earned runs allowed. solve the equation for e. what is a pitcher's era if he allows 57 earned runs in 63 innings pitched? if necessary, round your answer to the nearest hundredth.

Ben bowled 124 and 188 in his first two games. what must he bowl in his third game to have an average of at least 160?

Thales was an ancient philosopher familiar with similar triangles. one story about him says that he found the height of a pyramid by measuring its shadow and his own shadow at the same time. if the person is 5-ft tall, what is the height of the pyramid in the drawing?

In a survey of 1015 adults, a polling agency asked, "when you retire, do you think you will have enough money to live comfortably or not. of the 1015 surveyed, 534 stated that they were worried about having enough money to live comfortably in retirement. construct a 90% confidence interval for the proportion of adults who are worried about having enough money to live comfortably in retirement.