Prove every infinite set is equinumerous with a proper subset of itself

Can a trapezoid have four obtuse angles

Suppose a college surveyed its students and found that two-thirds of them sleep at least seven hours each night. on a campus of 918 students, how many students could be expected to sleep at least seven hours each night?

Examples of properties communative, associative, and identity?

P (x) = 4x^4+8x^3-7x^2-21x-9 what is the rational zero

If the length of a rectangle, originally 4cm by 2cm, is increased by x, what is the perimeter and area of the new rectangle

If 3 3/4 lb. of candy cost $20.25, how much would 1 lb. of candy cost?

carrie started with 12 ounces of water when she began her walk when she finished walking she had 2 1/4 ounces of water left how much water did she drink

William earns $15 each time (t) he mows a lawn. Which equation can be used to determine how many lawns William mowed if he earned $75?

What is the historical estimate of beta for your stock? what is the range of the estimate with 67% probability? with 95% probability?

A pet store had 6 puppies selling for 104 each and 12 kittens selling for 24 each. Today only 2 puppies and 8 kittens were left. In dollar terms, what was the ratio of the sales of puppies to kittens?