Answer :
Supposing that 20 out of 100 people choose black or gray, the percentage is of 20%.
What is a percentage?
The percentage of an amount a over a total amount b is given by a multiplied by 100% and divided by b, that is:
[tex]P = \frac{a}{b} \times 100\%[/tex]
Hence, if 20 out of 100 people choose black or gray, the percentage is given by:
[tex]P = \frac{20}{100} \times 100\% = 20\%[/tex]
More can be learned about percentages at https://brainly.com/question/10491646
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