How Do You Figure Out Whether a Percent of Change is an Increase or a Decrease?

'amt of chg' means amount of change
'orig amt' means orignal amount
'percent of change',' % of change', and '%chg' are all used to mean the same thing in this tutorial
%chg over 100 results in a percent
'final amt' means final amount
The cross products are (-131)•(100) and (362)•(% of Change)
'%chg' is the variable we need to get by itself
Dividing both sides by the same thing keeps the equation balanced.

1. 'percent of change',' % of change', and '%chg' are all used to mean the same thing in this tutorial
1. 'amount of change' or 'change' refer to the same thing in this tutorial
2. 362 is the original amount
3. 231 is the final amount
4. Since our final amount is less than our original amount, we know that our amount of change will be negative!
5. 231-362= -131 is the amount of change
1. 'percent of change' is what we're trying to find
1. We plug in for the amount of change, and the original amount!
1. Cross multiplication is sometimes called the means-extremes property of proportions
2. We need to get '% of Change' by itself
3. We get (-131)•(100) and (362)•(% of Change) as the cross products
1. '% of change' is one variable
2. First simplify the left-hand side
3. Then move 362 to the other side
4. Dividing both sides by the same thing keeps the equation balanced.
1. percent of change is -36.2% which is negative, therefore a decrease

When Jose was 10 years old, he had 362 baseball cards. Over the years he lost some cards and now, 20 years later, his collection contains only 231 cards. Find the percent of change and determine whether it is an increase or decrease.