Marissa earned $560 in the summer. she earned $40 each week for part of the summer and $60 each week for the rest. if she earned $40 each week twice as often as she earned $60, how many weeks did she earn $40?

12 point are triangles pqr and stu congruent? what is the congruency that proves they are congruent? what is the perimeter of triangle pqr?

Miguel’s teacher asks him to color 4/8 of his grid. he must use 3 colors: red, blue, and green. there must be more green sections than red sections. how can miguel color all the sections of his grid to follow all the rules

The first-serve percentage of a tennis player in a match is normally distributed with a standard deviation of 4.3%. if a sample of 15 random matches of the player is taken, the mean first-serve percentage is found to be 26.4%. what is the margin of error of the sample mean? a. 0.086% b. 0.533% c. 1.11% d. 2.22%