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PLEASE HELP!!!!!! A spinner is divided into many sections of equal size. Some sections are red, some are blue, and the remaining are green. The probability of the arrow landing on a section colored red is 9 over 20. The probability of the arrow landing on a section colored blue is 6 over 20. What is the probability of the arrow landing on a green-colored section?

15 over 20
11 over 20
6 over 20
5 over 20

User Deruse
by
3.1k points

2 Answers

3 votes

Answer:

15/20

Step-by-step explanation:

User Sukanta Paul
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3.6k points
7 votes

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.

User Vasiliy Stavenko
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4.3k points