When Zahra runs the 400 meter dash, her finishing times are normally distributed with a mean of 84 seconds and a standard deviation of 1.5 seconds. Using the empirical rule, what percentage of races will her finishing time be between 81 and 87 seconds?

Find the difference (8ab+a+2) - (3ab+6)

Can some one explain how to slove specifically, what is the value of x? 0.9(x+1.4)-2.3+0.1x=1.6 enter the answer as a decimal in the box. x= ?

40) linda was making chocolate truffles for the first day of school. the recipe for 20 chocolate truffles is: i cup of cream 2 cups of dark chocolate she noticed this will not be enough truffles for the 42 sure that all students in each homeroom next year. to be sure that all students receive a truffle, linda must adjust her recipe. a. complete the recipe for 42 truffles cups of cream - cups of dark chocolate work: