Let \( x \) be the number of brochures ordered.
The total cost for Company A can be expressed as: \[ \text{Cost}_A = 25 + 0.20x \]
The total cost for Company B can be expressed as: \[ \text{Cost}_B = 0.30x \]
We want to find the value of \( x \) for which Company A's cost is greater than Company B's cost: \[ 25 + 0.20x > 0.30x \]
Now, we can solve the inequality. First, subtract \( 0.20x \) from both sides: \[ 25 > 0.30x - 0.20x \]
This simplifies to: \[ 25 > 0.10x \]
Next, to isolate \( x \), divide both sides by 0.10: \[ x < \frac{25}{0.10} \] \[ x < 250 \]
Thus, Company A costs more than Company B when the number of brochures ordered is less than 250.
To find the number of brochures for which Company A costs more than Company B, we can also check at \( x = 250 \): At \( x = 250 \):
- Cost of Company A: \[ \text{Cost}_A = 25 + 0.20(250) = 25 + 50 = 75 \]
- Cost of Company B: \[ \text{Cost}_B = 0.30(250) = 75 \]
At \( x = 250 \), both costs are equal. Therefore, Company A starts to be more costly than Company B for \( x = 251 \) or more.
In conclusion, Company A costs more than Company B when the number of brochures ordered is:
\[ \boxed{251} \] or more.