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4 votes
What percent?

What percent of the first 20 natural numbers are prime numbers?

User Papey
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2 Answers

4 votes
Let's find all the prime numbers.

1,3,5,7,9,11,13,15,17,19

They are not divisible by 2.

Put that into a fraction, where the amount of numbers is the numerator and the total amount of numbers is the denominator.

10/20

That is half of 20.

So, 50% of the 20 first natural numbers are prime.

I hope this helps!
~cupcake
User Anastasia Black
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7.1k points
4 votes
Prime numbers: 2, 3 , 5, 7, 11, 13, 17, 19= 8/20 numbers.
8/20= 4/10 4/10=2/5
2/5= 40%
User Stratos
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6.0k points