Maria has 8 red pens.
She has 10 more black pens than red pens, so she has 8 + 10 = 18 black pens.
She also has 7 more blue pens than red pens, so she has 8 + 7 = 15 blue pens.
In total, Maria has 8 + 18 + 15 = 41 pens.
#### 41
The answer is: 41
Below is a math problem. Provide a detailed, step-by-step solution.

### Problem:
There are 8 red pens in Maria's desk drawer. There are 10 more black pens than red pens. There are also 7 more blue pens than red pens. How many pens are there in all?

### Answer:
