To find out how much food one dog eats in one day, we can start by determining the total amount of food consumed per dog per day.
Given:
- 3 dogs eat 30 pounds of food in 10 days.
First, we calculate the total amount of food consumed per day by all three dogs:
\[ \text{Total food per day} = \frac{30 \text{ pounds}}{10 \text{ days}} = 3 \text{ pounds per day} \]
Next, since there are 3 dogs, we can find out how much food one dog eats in one day by dividing the total food consumed per day by the number of dogs:
\[ \text{Food per dog per day} = \frac{3 \text{ pounds}}{3 \text{ dogs}} = 1 \text{ pound per dog per day} \]
Therefore, each dog eats 1 pound of food in one day.
The correct answer is 1 pound.