Solve using short cut methods: `783+9999`

Answer

To solve the problem \( 783 + 9999 \) using a shortcut method, we can follow these steps:

### Step-by-Step Solution:

1. **Rewrite the Addition**:
We can express \( 9999 \) as \( 10000 - 1 \).
So, the equation becomes:
\[ 783 + 9999 = 783 + (10000 - 1) \]

2. **Simplify the Expression**:
Now, we can simplify the expression:
\[ 783 + 10000 - 1 \]

3. **Calculate \( 783 + 10000 \)**:
Adding \( 783 \) and \( 10000 \):
\[ 783 + 10000 = 10783 \]

4. **Subtract 1**:
Now, we subtract \( 1 \) from \( 10783 \):
\[ 10783 - 1 = 10782 \]

5. **Final Answer**:
Thus, the final result of \( 783 + 9999 \) is:
\[ \boxed{10782} \]