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The brain volumes (cm cubed) of 50 brains vary from a low of 904 cm cubed to a high of 1488 cm cubed. use the range rule of thumb to estimate the standard deviation s and compare the result to the exact standard deviation of 175.5 cm cubed, assuming the estimate is accurate if it is within 15 cm cubed

Determine the difference: 3.2 × 1010 – 1.1 × 1010. write your answer in scientific notation.

Last week , donnell practiced the piano 3 hours longer than marcus . together, marcus and donnell practiced the piano 11 hours . for how many hours did each young man practiced the piano