For the following set of data, find the number of data within 1 population standard deviation of the mean. Data Frequency 15 1 16 7 17 11 21 13 22 12 25 9 28 6 30 1 i need this quckly please
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You are constructing a histogram for scores that range from 70 to 100 in whole points. frequencies range from 3 to 10; that is, every whole-point score between 60 and 100 occurs at least 3 times, and at least one score occurs 10 times. which of these would probably be the best range and size for the score intervals along the x-axis?

Which equation results from adding the equations in this system? x+6y=9 and -x+2y=-15

Can some one explain this i got sent this. is this a threat i’m scared