With a mean of 55 and a standerd deviation of 9 what is the value of three standard deviations to the right

Over which interval is the graph of f(x) = x2 + 5x + 6 increasing?

Robin spent 25% more time on his research project than he had planned he’s been an extra h ours on the project which of the following expressions could represent the number of hours rob actually spent on the project

Last week , donnell practiced the piano 3 hours longer than marcus . together, marcus and donnell practiced the piano 11 hours . for how many hours did each young man practiced the piano