a + b +c = 75; where a is the greatest number; b is the middle number; c is the least number;
a = 2 * c;
b = 3 + c;
then, 2 * c + 3 + c + c = 75 => 4 * c = 72 => c = 72 / 4 => c = 18 => a = 2 * 18 => a = 36; b = 3 + 18 => b = 21;
The three numbers Jabary is thinking of are 36 (greatest number), 21 (middle number), and 18 (least number). Each of these numbers satisfies the given conditions of the problem. The sum of these numbers equals 75, confirming their correctness.
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