Arthur has 3 dogs. They eat an average of 15 pounds of food a week. One dog eats 13 pounds a week. The second eats double this. How much does the third dog eat a week?
The second dog eats 26 pounds a week because 13 x 2 = <<13*2=26>>26
In total they eat 45 pounds because 3 x 15 = <<3*15=45>>45
The third dog eats 6 pounds a week because 45 - 13 - 26 = <<45-13-26=6>>6
#### 6