Answer: D) 5 over 20
This is the same as writing 5/20
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Step-by-step explanation:
Instead of saying "9 over 20", I'll write 9/20. The same goes with the other fractions.
The 9/20 probability for red means there are 9 red out of 20 total.
Similarly, the 6/20 refers to 6 blue out of 20 total.
There are 9+6 = 15 sections that are either red or blue, but not both.
This leaves 20-15 = 5 sections for green and it leads to 5/20 as the final answer. We could reduce 5/20 to get 1/4, but it looks like your teacher doesn't want you to reduce the fraction. Sometimes it's handy to not reduce because we see that it's out of 20 spaces total.