If you write

, you'll notice this is really just a quadratic equation that can be factorized:

So you have

and
Answer:
78.5
Step-by-step explanation:
pi r^2
22/7 * 5^2
Turn the question around.
If all the numbers were positive: 2.5, 1.6, 3 1/10, 1/10, and 0.5, which would be farthest to the right?
The fact is that the negative numbers are a reflection of the positive numbers.
Since 3 1/10 would be farthest to the right with positive numbers, -3 1/10 will be farthest to the left with the negative numbers.