Eduardo thinks of a number between 1 and 20 that has exactly 5 factors. What number is he thinking of?
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i didn't see it im sorry i will look back
Eduardo thinks of
To find the number Eduardo is thinking of, we need to determine a number that has exactly 5 factors.
To do this, we can first list out the prime numbers between 1 and 20: 2, 3, 5, 7, 11, 13, 17, 19.
To have exactly 5 factors, the number must either be a perfect square of a prime number or the product of two distinct prime numbers.
Let's check the prime numbers first:
2 has 2 factors: 1 and 2.
3 has 2 factors: 1 and 3.
5 has 2 factors: 1 and 5.
7 has 2 factors: 1 and 7.
11 has 2 factors: 1 and 11.
13 has 2 factors: 1 and 13.
17 has 2 factors: 1 and 17.
19 has 2 factors: 1 and 19.
None of the prime numbers between 1 and 20 have exactly 5 factors.
Now, let's check the product of two distinct prime numbers:
2 x 3 = 6. Number 6 has 4 factors: 1, 2, 3, and 6.
2 x 5 = 10. Number 10 has 4 factors: 1, 2, 5, and 10.
2 x 7 = 14. Number 14 has 4 factors: 1, 2, 7, and 14.
2 x 11 = 22. Number 22 has 4 factors: 1, 2, 11, and 22.
2 x 13 = 26. Number 26 has 4 factors: 1, 2, 13, and 26.
2 x 17 = 34. Number 34 has 4 factors: 1, 2, 17, and 34.
2 x 19 = 38. Number 38 has 4 factors: 1, 2, 19, and 38.
None of the products of two distinct prime numbers between 1 and 20 have exactly 5 factors.
Now, let's check the perfect squares of the prime numbers:
2 squared is equal to 4. Number 4 has exactly 3 factors: 1, 2, and 4.
3 squared is equal to 9. Number 9 has exactly 3 factors: 1, 3, and 9.
5 squared is equal to 25. Number 25 has exactly 3 factors: 1, 5, and 25.
7 squared is equal to 49. Number 49 has exactly 3 factors: 1, 7, and 49.
11 squared is equal to 121. Number 121 has exactly 3 factors: 1, 11, and 121.
13 squared is equal to 169. Number 169 has exactly 3 factors: 1, 13, and 169.
17 squared is equal to 289. Number 289 has exactly 3 factors: 1, 17, and 289.
19 squared is equal to 361. Number 361 has exactly 3 factors: 1, 19, and 361.
None of the perfect squares of the prime numbers between 1 and 20 have exactly 5 factors.
Since none of the numbers we have checked so far have exactly 5 factors, it seems Eduardo may have made a mistake or misunderstood the criteria.