You are selling T-shirts to raise money for charity you sell T-shirt for $10 and you have already sold 2 of them how many more T-shirts much do you sell to raise at least $500

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