Question

Use additive inverse to find -123.45 - (-234.76)

Answer 1

To find \(-123.45 - (-234.76)\) using the concept of additive inverse, we can rewrite the expression. The additive inverse of a number \(x\) is \(-x\). Therefore, subtracting a negative number is the same as adding its positive.

Thus, we can rewrite the expression as follows:

\[
-123.45 - (-234.76) = -123.45 + 234.76
\]

Now we perform the addition:

\[
-123.45 + 234.76
\]

Aligning the numbers for addition:

```
234.76
- 123.45
_________
```

Starting from the rightmost decimal place:

1. **Hundredths place**: \(6 - 5 = 1\)
2. **Tenths place**: \(7 - 4 = 3\)
3. **Units place**: \(4 - 3 = 1\) (taking 2 as 20 + 10)
4. **Tens place**: \(2 - 1 = 1\) (2 is left after borrowing)
5. **Hundreds place**: \(0 + 2 = 2\)

Putting everything together, we have:

\[
234.76 - 123.45 = 111.31
\]

Thus, the final result is:

\[
-123.45 - (-234.76) = 111.31
\]