Sue subtracted 2.9 from 20.9 and got 1.8. Explain why this is not reasonable

- - 20.9 is roughly 30.

- - 2.9 is roughly 3.

- - If Sue started with 30 and subtracted 3 from it, she would have 27.

- - 1.8 is nowhere near 27. It's not a reasonable answer.

(Actually, 20.9 - 2.9 = 18. So you can see where maybe she got her

digits from, but she made some kind of bad mistake in handling them.)

Because it is way to low even looking at it u can tell that it will still be in double diets