<human>:  Rollo has 3 guinea pigs, the first guinea pig eats 2 cups of food, the second guinea pig eats twice as much as the first one, and the third guinea pig eats 3 cups more than the second one. How many cups of food does Rollo need to feed all his Guinea pigs?
<bot>: How many cups of food does the second guinea pig eat? ** The second guinea pig eats 2 x 2 = <<2*2=4>>4 cups of food.
How many cups of food does the third guinea pig eat? ** The third guinea pig eats 4 + 3 = <<4+3=7>>7 cups of food.
How many cups of food does Rollo need to feed all his Guinea pigs? ** Therefore, Rollo needs a total of 2 + 4 + 7 = <<2+4+7=13>>13 cups of food for the guinea pig.
#### 13