Joseph’s lunch at the diner costs $15 without tax. He left the waiter a 21% tip. What was his total cost of the lunch, including tip, without tax?

Factor the expression using gcf 9b+45

Scores on the cognitive scale of the bayley-scales of infant and toddler development range from 1 to 19, with a standard deviation of 3. calculate the margin of error in estimating the true mean cognitive scale score, with 99% confidence, if there are 12 infants and toddlers in a sample.

Tanyss's house has 25 windows. her brother has washed 22 of the windows. what percent of the windows has her brother washed?