Question

Choose 2 numbers whose sum is -2.6.
0.7
0.3
1.0
-2 9/10
0.8
-3 3/10
-3 2/5
-18/5

Answer 1

To find two numbers from the list that add up to -2.6, we can convert -2.6 to a fraction for easier addition:

-2.6 = -26/10 = -13/5.

Now let's check each possible pair of numbers from the list to see if any of them add up to -13/5.

Here are the numbers again in decimal or improper fraction format:

- \(0.7\)
- \(0.3\)
- \(1.0\)
- \(-2 \frac{9}{10}\) = -2.9
- \(0.8\)
- \(-3 \frac{3}{10}\) = -3.3
- \(-3 \frac{2}{5}\) = -3.4
- \(-\frac{18}{5}\) = -3.6

Calculating pairs:

1. \(0.7 + (-2.9) = 0.7 - 2.9 = -2.2\)
2. \(0.7 + (-3.3) = 0.7 - 3.3 = -2.6\) ✔
3. \(0.7 + (-3.4) = 0.7 - 3.4 = -2.7\)
4. \(0.3 + (-2.9) = 0.3 - 2.9 = -2.6\) ✔
5. \(1.0 + (-2.9) = 1.0 - 2.9 = -1.9\)
6. \(0.8 + (-2.9) = 0.8 - 2.9 = -2.1\)
7. \(0.3 + (-3.3) = 0.3 - 3.3 = -3.0\)
8. \(0.3 + (-3.4) = 0.3 - 3.4 = -3.1\)
9. \(1.0 + (-3.3) = 1.0 - 3.3 = -2.3\)
10. \(1.0 + (-3.4) = 1.0 - 3.4 = -2.4\)

The pairs that sum to -2.6 are:

- \(0.7\) and \(-3.3\)
- \(0.3\) and \(-2.9\)

So, two valid pairs of numbers from your list that sum to -2.6 are:

- \(0.7\) and \(-3.3\)
- \(0.3\) and \(-2.9\)