Pencils come in boxes of 10. how many boxes should erika buy if she needs 127 pencils?

What is the standard deviation of the following data set rounded to the nearest tenth? 3, 17, 18, 15, 12, 21, 9

Cody was 165cm tall on the first day of school this year, which was 10% taller than he was on the first day of school last year.

Apassenger train and a freight train leave san jose at 3pm, traveling in the same direction. the passenger train is going three times as fast as the freight train. at 6pm they are 240 miles apart. how fast is each travelling? explain your answer and show your