Question

Kelly subtracted 2.3 from 20 and got 17.7. explain why this answer is reasonable

Answer 1

The correct answer to this is that 2.3 -20=-17.7 the answer is resonable because if you go on a number line then you would see that if you start a 2.3 and subtract 20 spaces you get to ----17.7

Answer 2

If 20-2.3=17.7, then if you add 17.7 to 2.3. it equals 20 which is called the communicative property because whatever you add or subtract, the answer is the same
17.7+2.3=2.3+17.7