12 + 42 + 72 + + (3n - 2)2 = quantity n times quantity six n squared minus three n minus one all divided by two

Eileen purchased 3.4 pounds of apples at the total cost of $19.72. if she purchases 6.2 pounds of apples at this store, how much would it cost?

The number if marbles of different colors stored in a hat is listed below: 4 red marbles 10 green marbles 7 blue marbles. without looking in the hat, dan takes out a marble at random. he replaces the marble and then takes out another marble from the hat. what is the probability that dan takes out a blue marble in both draws?

Show your workcan a right triangle have this sides? *how to prove it without using the pythagorean theorema*