Answer:
if you meant x times y...
15 x 20 is 300.
if you meant x + y...
15 + 20 is 35.
if you meant anything else, please let me know
the way it was written confused me but I tried.
Ok, let's find how much does 1 yard of ribbon cost. Let's divide!

Each yard costs $1.50, so let's multiply that by 10

Marci will pay $15 for 10 yards of the ribbon.
Answer:
18.95%
Step-by-step explanation:
In this case what we must do is calculate the probability of eating a jelly treats first and then another jelly treats, being the final probability the multiplication of these events.
We know that there are 20 in total and that initially there are 9 jelly treats, so the first event is the probability:
9/20
And the second event, with one less in each, would be:
8/19
The final probability then:
9/20 * 8/19 = 0.1895
So the probability of this happening is 18.95%
The answer is (4x20) + (4x4) which equals 96