Answer: 90% decrease
Step-by-step explanation: First determine whether the number is increasing or decreasing. Since it changes from 2,000 to 200, it's going down so it's decreasing.
Now to find the percent decrease, we divide the
amount of change by the original number.
The amount of change is the difference between the two numbers
which in this case is 2,000 - 200 and the original number is 2,000.
.
2,000 - 200 is 1,800.
So we're left with 1,800/2,000 and dividing
2,000 into 1,800 gives us 0.9.
Remember however that our problem is
asking for a percent, not a decimal.
So we need to write 0.9 as a percent and we can do
that by multiplying it by 100 and adding the percent sign.
So 0.9 becomes 90%.
So when a number changes from 2,000 to 200,
it has decreased by 90%.