Solve the Addition Problem: Finding the Sum of 43 + 51

To solve the addition problem $43 + 51$, we'll follow these steps:

• Step 1: Align the numbers vertically by their place value (units, tens).
• Step 2: Start adding from the rightmost column, which is the units column, and proceed to the leftmost column (tens).

Let's perform the addition:
Step 1: Align the numbers:
    43
+  51
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Step 2: Add the units column: $3 + 1 = 4$. Write 4 in the units place.
Add the tens column: $4 + 5 = 9$. Write 9 in the tens place.

Thus, the sum of 43 and 51 is $94$.

The correct answer is $94$, which corresponds to choice 1.