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If f(x)=3x+1 and f^-1=x-1/3, then f^-1(7)=

Atriangle with all sides of equal length is a/an triangle. a. right b. scalene c. equilateral d. isosceles

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?