What is 21 over 40 in percent

15 students are going on a field trip. if three-fifths of them pack their lunches, how many students pack their lunches

A box contains 24 light bulbs, of which four are defective. if a person selects four bulbs from the box at random, without replacement, what is the probability that all four bulbs will be defective?

If ef = 6 and eg = 21 what is the value of fg

Factor 4n^4 + n^3. A. n (4n^3 + 1) B. n^3 (4n + 1) C. n^3 (4n)

How can 2x2 = x2 + 4x + 8 be set up as a system of equations? y = x2 - 4 y = x2 + 2x + 8 y = x2 y = x2 + 4x + 8 y = 2x2 y = x2 + 4x + 8 y = x2 y = 2x + 8

the sum of the digits of a two-digit number is 9. when the digits are reversed, the new number is 9 more than the original number. find the original number. check your answer.

Prove that if a, b and c are odd integers such that a + b + c = 0, then abc < 0. (you are permitted to use well-known properties of integers here.) be sure to show all work.

The cost of one pound of peanuts is 60% of the cost of one pound of cashews. If one pound of cashews costs $2, what is the cost of one pound of peanuts? What is the total cost of two pounds of peanuts and one pound of cashews?

Whats the fuction that represents a geometric sequence

Emily is 50 years old. Colin is 18 years older than Emily. Dan is 6 years younger than Emily. What is the total of their combined ages?