One day, eleven babies are born at a hospital. assuming each baby has an equal chance of being a boy or girl, what is the probability that at most nine of the eleven babies are girls?
a.
23/256
b.
191/256
c.
509/512
d.
397/2048

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