## greeneyes<3 2 years ago Find the percent of change. From 4000 ft^2 to 3990 ft^2 (my answer: 1%) Check/correct my answer? :)

1. Xavier

How did you get that value?

2. greeneyes<3

i divided 3990/4000, and rounded .9975 to 1%

3. Xavier

To find the percent change is to see how much the value changed compared to the old value. $\%\ change = \frac{new-old}{old}*100$ Also 0.9975 is 99.75% which would round to 100% which is wrong.

4. greeneyes<3

okay thank you this makes much more sense!!! I havent done alg in a year...

5. greeneyes<3

6. Xavier

You did the equation correctly but interpreted it incrorrectly. The equation takes care of converting from decimal value to percent. So when you got 0.25 that did not mean 25% but 0.25%. You can remove the 100 from the equation above to make it return the decimal

7. greeneyes<3

oh okay so .25% ?

8. Xavier

It may have been negative but I believe percent change is taken as the absolute value so that should be fine.