Each shape in this number sentence stands for a different number.

This number sentence is true:

Select the two number sentences below that must also be true.

The balance beam shows that 3 pears have the same weight as one orange.
 

 
How many pears balance 2 oranges and 1 pear?

The rule below results in the following table.

What is the missing number in the table?

In this number sentence, both circles represent the same number.

What number does  represent?

What number makes the above number sentence correct?