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Percentage Increase/Decrease

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Percentage Increase/Decrease, a selection from the Dr. Math archives.

Percentage of Increase
What is the percent of increase when you go from 96 to 256?

Finding Percentage of Increase
Find the percentage increase: old, $50.50; new $75.75.

Percentage of Increase
I need to figure out a percent increase: the figure in 1995 was 50,000 and the estimated figure for 2000 is 325,000.

Percentage Target (Projection)
I am trying to work out percentage difference between a given figure and a projected figure in the future.

Percentage Increase in Cost of Eggs
When eggs went from 17 to 39 cents, by what percent did the price increase?

Percentage Increase vs. Percentage
If there were 10,000 claims in 2001, and that is a 300 percent increase since 1999, how many claims were there in 1999?

Percentage of Decrease
If last year I collected 500 cans and this year I only collected 350 cans, what would be my percentage of decrease for this year?

Percent Change, Increase, Difference
How do you find the percent difference between two numbers? What about percent change and percent increase?

Figuring Percentage of Increase
In 1990, Allen County, Kansas, had 14,385 people. Now, in 2001, it contains 14,905 people. How do I calculate the increase, using a percentage?

How Much Water Evaporated?
A substance is 99% water. Some water evaporates, leaving a substance that is 98% water. How much of the water evaporated?

Percent Greater Than vs. Increased
Is there a difference between the following statements? My profits are 200% greater than they were last year; My profits from last year have increased 200%.

Duelling Percentages
Why doesn't a decrease of 15%, followed by an increase of 15%, get you back to where you started?

Undoing Percentage Changes
If I increase an initial amount by P percent, by what percentage would I have to decrease it to get back to where I started?

Calculating Percent Change when the Base is a Negative Number
In preparing financial statements, I must calculate the percent change of the net income between years...

When Percentage Calculations are Inappropriate
How do I best calculate the percentage of goal when at least one of the numbers is a negative number?

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