SOLUTION: Marco is in elementary school. His father is 30 years older than Marco, and his mother is 4 years younger than his father. The ages of Marco, his mother, and his father are all pri
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-> SOLUTION: Marco is in elementary school. His father is 30 years older than Marco, and his mother is 4 years younger than his father. The ages of Marco, his mother, and his father are all pri
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Question 1169871: Marco is in elementary school. His father is 30 years older than Marco, and his mother is 4 years younger than his father. The ages of Marco, his mother, and his father are all prime numbers. What are their ages?
Since the question involves prime numbers, there is no simple algebraic way to solve the problem; you can find answers by trial and error.
Note that the conditions almost certainly allow multiple possible answers; many of them of course won't make sense since they represent people's ages.
So it is impossible to find "THE" answer to the problem.
The requirements are:
(1) Marco's age is a prime number x;
(2) his father's age is a prime number x+30; and
(3) his mother's age is a prime number x+26
So simply choose a prime number for Marco's age and see if it results in prime number ages for his father and mother.
Marco father mother
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3 33 29 no
5 35 31 no
7 37 33 no
11 41 37 YES
13 43 39 no
17 47 43 YES
19 49 45 no
23 53 49 no
29 59 55 no
31 61 57 no
37 67 63 no
41 71 67 YES
...
101 131 127 YES -- but not reasonable!
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