40+56; if a = 1/2; 6 = 5

Empty box + box + empty box fill in the box is equal to 30 how

He weights of 2-pound bags of best dog food are approximately normally distributed with a given mean  and standard deviation  according to the empirical rule, what percentage of the bags will have weights within 3 standard deviations of the mean? 47.5%68%95%99.7%

The difference of three and the reciprocal of a number is equal to the quotient of 20 and the number. find the number.