If you subtract 12-7.28 what is your answer ?

You were told that the amount of time lapsed between consecutive trades on the new york stock exchange followed a normal distribution with a mean of 15 seconds. you were also told that the probability that the time lapsed between two consecutive trades to fall between 16 to 17 seconds was 13%. the probability that the time lapsed between two consecutive trades would fall below 13 seconds was 7%. what is the probability that the time lapsed between two consecutive trades will be between 14 and 15 seconds?

What are the solutions of the system? solve by graphing. y = -x^2 -6x - 7 y = 2

The measure of an angle is 117°. what is the measure of a supplementary angle?