Question

How should you group the following expression to make it easiest to add?
4
7
18 − 9 + − 8
9
9
( 1 point)
(18 − 8 − 9)
7
(8 − 18) + ( + )4
9
9
7
(18 − 9 − 8) + (− + )4
9
9
7
(18 − 8) + (−9 + )4

Answer 1

To make the expression easiest to add, you should focus on grouping the terms in a way that simplifies the arithmetic.

Let's analyze the options:

- **Grouping the first expression "18 − 9 + − 8":**
- If we calculate it step by step, we can see it as:
\[
18 - 9 - 8 = 1
\]
So if we simplify this together with \(4\), \(7\), and the \(9\)s, it won't make the addition easier.

- **Grouping "(18 − 8 − 9)":**
- This simplifies to:
\[
18 - 8 - 9 = 1
\]
Bringing us back to the same starting point.

- **Grouping "(8 − 18) + ( + )4":**
- This option is less straightforward and doesn't lead to a clear addition.

- **Grouping "(18 − 9 − 8) + (− + )4":**
- This reduces to:
\[
18 - 9 - 8 = 1
\]
Again returning to a similar sum.

- **Grouping "(18 − 8) + (−9 + )4":**
- Evaluating this:
\[
18 - 8 = 10
\]
And we'd grow complex with the negative which may confuse the addition further.

### Recommended Grouping:
The first option of simplifying "(18 - 9 - 8)" typically leads to the easiest calculation.

### Thus:
- The expression with the simplest sum is:
- **(18 - 9 - 8) + 4 + 7 + 9 + 9**
- Which simplifies to **1 + 4 + 7 + 9 + 9 = 30**.

This grouping makes the math straightforward and you can calculate it quickly.