I believe the answer is 20 hope this helped!
<span>One <u>possible model</u><span> is:
You could place 3 red marble and 1 blue marble in a bag. The probability of drawing a red marble would be 3/4, which is 75%; this means red marbles would be sunny days and blue marbles would be cloudy days.
Each draw out of the bag would represent one day of the week. Draw a marble 7 times, replacing it after each draw. This would represent the weather for the days of the week.</span></span>
Starting from what I know (the difference between ribbons), I decided to go from the bottom and work my way up. I then noticed a pattern (each sum was three more of the previous one), and decided to keep my pattern of the three numbers but not have to do any major mental work and instead add three to the previous sum until I got to 38.
I think the answer is C. 5x8x2.5=100