Solve Vertical Addition: 72 + 7 Step by Step

To solve this problem, we'll follow these steps of vertical addition:

• Step 1: Align the numbers such that the units are directly under each other:

$\begin{array}{r} 72 \\ + 7 \\ \hline \end{array}$

• Step 2: Add the units column. The units are 2 and 7.

Calculation: $2 + 7 = 9$. The result for the units column is 9.

• Step 3: Add the tens column. The tens are 7 with no carry from the previous step.

Calculation: $7 + 0 = 7$. The result for the tens column remains 7.

• Step 4: Combine both results:

Therefore, the sum is $79$.

Hence, the final answer is $79$. The correct choice is option 3.