First, I'll translate the problem into English:
Amy has four gerbils whose masses are 20 g, 22 g, 24 g, and 26 g.
What is the total mass of the gerbils in milligrams?
First add the masses in grams:
20 g + 22 g + 24 g + 26 g = 92 g
Now convert grams into milligrams.
1 gram = 1000 milligrams
92 g * 1000 = 92,000 mg
Answer: The total mass is 92,000 mg.