Diego, Kiran, and Clare were wondering:

“If Neptune and Saturn were side by side, would they be wider than Jupiter?” 

1. They start by trying to add km and km, the diameters of Neptune and Saturn. Here are the ways they approached the problem. Do you agree with any of them? Explain your reasoning.

   1. Diego says, “When we add the distances, we will get . The exponent will be 9. So the two planets are km side by side.”
      
       

   2. Kiran wrote as 49,000 and as 120,000 and added them: 

   3. Clare says, “I think you can’t add unless they are the same power of 10.” She adds and to get .
      
       

1. When you add the distances from the Sun of Mercury, Venus, Earth, and Mars, would you reach as far as Jupiter? Explain or show your reasoning.

2. Add the diameters of all the objects on the table except the Sun. Which is wider, all of these planets side-by-side, or the sun? Explain or show your reasoning.

The table shows the average mass of one individual creature and an estimated total number of those creatures on Earth. Use the table to answer each question, and explain or show your reasoning. 

1. On a farm there was a cow. And on the farm there were 2 sheep. There were also 3 chickens. What is the total mass of the 1 cow, the 2 sheep, the 3 chickens, and the 1 farmer on the farm?

2. What is the total mass of a human, a blue whale, and 6 ants all together?
3. Which is greater, the number of bacteria, or the number of all the other animals in the table put together?