What number is missing in the equation 6 + ___ = 10?

• A. 2
• B. 3
• C. 4
• D. 5

Answer: (C)

To determine the missing number in the equation 6 + ___ = 10, we need to find the value that, when added to 6, results in the total of 10. This is a basic arithmetic problem that involves understanding addition and the concept of "what number makes it complete."

Start with the number 6. If we need to reach a total of 10, we can think of it as setting up an equation where the unknown adds up to the total. The equation can be rearranged to find the missing value:

Missing number = Total - Known number

Missing number = 10 - 6

Missing number = 4

Therefore, the number that completes the equation is 4, as adding 4 to 6 gives us exactly 10. This illustrates the principle of solving a simple addition equation by determining what number is required to reach a given sum.