Two mechanics worked on a car. the first mechanic worked for 10 hours, and the second mechanic worked for 15 hours. together they charged a total of $2350 . what was the rate charged per hour by each mechanic if the sum of the two rates was $175 per hour?

Pj is decorating pupcakes for rocky's birthday party. her color scheme is black, purple, and green. she will use this spinner to determine the color of sprinkles on each pupcake. which model shows the probability of randomly landing on each color?

At the olympic games, many events have several rounds of competition. one of these events is the men's 100-meter backstroke. the upper dot plot shows the times (in seconds) of the top 8 finishers in the final round of the 2012 olympics. the lower dot plot shows the times of the same 8 swimmers, but in the semifinal round. which pieces of information can be gathered from these dot plots? (remember that lower swim times are faster.) choose all answers that apply: a: the swimmers had faster times on average in the final round. b: the times in the final round vary noticeably more than the times in the semifinal round. c: none of the above.

1jessica's home town is a mid-sized city experiencing a decline in population. the following graph models the estimated population if the decline continues at the same rate. select the most appropriate unit for the measure of time that the graph represents. a. years b. hours c. days d. weeks