Frank works in the supply room of a law firm. At the beginning of the month, he had 21 boxes of pens with 13 pens in each box. At the end of the month, there were 45 pens left. How many pens did he give out over the month?

Which of the fallowing best completes the sequence 5,10,15, a) 30 b) 22 c)25 d)35

Is the product of two rational numbers irrational or rational? first, make a hypothesis by multiplying two rational numbers. then, use variables such as x=a/b and y=c/d and the closure property of integers to prove your hypothesis.

Weekly wages at a certain factory are normally distributed with a mean of $400 and a standard deviation of $50. find the probability that a worker selected at random makes between $450 and $500