Explain an example of how taking an amount (for example, $20), decreasing it by 40% and then increasing that amount by 40% does not get you back to the original amount.

See below

Step-by-step explanation:

What we can do is try it out.

20*0.6=12

since 0.6 is left

now we increase 12 by 40, or multiply it by 1.4

12*1.4= 16.8

See what is happening here is that at first when we are decreasing it by 40 percent, we are taking 40 percent of 20. However, when we increase that amount by 40 percent, we are now increasing 40 percent of 20 by 40 percent, or increasing 16 by 40 percent. Therefore, we will not get the original amount.