In a classroom the probabilty that the teacher chooses a boy from a girl is 0.45. how many boys are there?

Dungeons and dragons uses a twenty-sided cube (dice), what is the probability that you will roll an even or odd prime number?

Venn diagram of 154 and 210

If 30% of a number is 15 what is the original number?

Alex has 5 pieces of paper, each with a different math problem. In how many ways can he give these problems to his 10 friends (he can give each friend more than one problem)

Specify three fractions with different denominators that have an LCD of 24

20/18+5/18 = what mixed fraction

A homogeneous linear system in 5 unknowns whose corresponding augmented matrix has a reduced row echelon form with 3 leading 1's will have free variables.

There are three routes from a person's home to her place of work. There are four parking lots where she works, three entrances into her building, two elevators to her floor, and one route from each elevator to her office door.

A scientist measures a substance to be 0.6 grams. Calculate the percent of error in the measurement. Show all work for full credit

Factor the trinomial completely 2x^5+16x^4+8x^2 2x 5 + 16x 4 + 8x 2