B. 75
First you find the area of the triangle:
(base x height)/2
(3 x 5)/2
15/2
7.5
Then you multiply by the length of the prism (10):
7.5 x 10 = 75
A polygon has 5 sides you can find the length of one side by dividing the total perimeter of 18 by the number of sides of 5. giving you 3.6
https://www.google.com/url?sa=t&source=web&rct=j&url=https://www.khanacademy.org/math/algebra/one-variable-linear-equations/alg1-intro-equations/v/variables-expressions-and-equations&ved=2ahUKEwjrpqD1gZziAhUBsp4KHVePBeEQwqsBMAB6BAgHEAU&usg=AOvVaw0AYOWzWFGI7vP8YUOvBhPc Here is a video that's helpful to me
At the start, you have 10 marbles in total and 6 red marbles. The probability of the first event is 6/10.
Since you do not place the marble back in, you now have 9 marbles in total and 3 blue marbles. This probability of the second event is 3/9.
To find the probability of both events occurring, we multiply the two probabilities together. (6•3)/(10•9)=18/90=1/5
Thus, there is a 20% chance of drawing a red marble then a blue marble without placing the red marble back in the bag.
