1. **State the problem:**
We have two numbers, one is positive and is 3 times the other. If we add 2 to the larger number and 5 to the smaller number, then one of the resulting numbers is twice the other. We need to find the smaller number.
2. **Define variables:**
Let the smaller number be $x$.
Then the larger number is $3x$.
3. **Write the conditions:**
After adding, the larger number becomes $3x + 2$ and the smaller number becomes $x + 5$.
One of these is twice the other, so either:
$$3x + 2 = 2(x + 5)$$
or
$$x + 5 = 2(3x + 2)$$
4. **Solve the first equation:**
$$3x + 2 = 2x + 10$$
Subtract $2x$ from both sides:
$$3x - 2x + 2 = 10$$
$$x + 2 = 10$$
Subtract 2:
$$x = 8$$
5. **Check if $x=8$ satisfies the problem:**
Smaller number = 8 (positive, valid)
Larger number = $3 imes 8 = 24$
Add 2 to larger: $24 + 2 = 26$
Add 5 to smaller: $8 + 5 = 13$
Check if one is twice the other: $26 = 2 imes 13$ (True)
6. **Solve the second equation:**
$$x + 5 = 2(3x + 2)$$
$$x + 5 = 6x + 4$$
Subtract $x$ from both sides:
$$5 = 5x + 4$$
Subtract 4:
$$1 = 5x$$
Divide by 5:
$$x = \frac{1}{5}$$
7. **Check if $x=\frac{1}{5}$ satisfies the problem:**
Smaller number = $\frac{1}{5}$ (positive, valid)
Larger number = $3 \times \frac{1}{5} = \frac{3}{5}$
Add 2 to larger: $\frac{3}{5} + 2 = \frac{3}{5} + \frac{10}{5} = \frac{13}{5}$
Add 5 to smaller: $\frac{1}{5} + 5 = \frac{1}{5} + \frac{25}{5} = \frac{26}{5}$
Check if one is twice the other: $\frac{26}{5} = 2 \times \frac{13}{5}$ (True)
8. **Conclusion:**
Both $x=8$ and $x=\frac{1}{5}$ satisfy the conditions, but since the problem states "a positive number is 3 times another number" and does not restrict to integers, both are valid. The smaller number can be either $8$ or $\frac{1}{5}$.
**Final answer:** The smaller number is either $8$ or $\frac{1}{5}$.
Smaller Number
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