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Learn the toughest concepts covered in Microeconomics with step-by-step video tutorials and practice problems by world-class tutors

Basic Principles of Economics

Percentage and Decimal Review

Have you forgotten about decimals and percentages? Let's get right to the point ;)

Calculating Percentage Change

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Alright. So now let's review how to calculate percentage change. So this is the amount that something has changed in percent. So if we started at 10 and now we are at 15, what is the percentage change from 10 to 15? This is going to be the formula that we use. So it's gonna be the church changing X over the original value of X. X. Being whatever we're trying to find the percentage change of. Right? So another way to think of the change in X. It's the new value for X minus the original value for X. Right? And we're going to divide that by the original value. So let's try this first example here. Um We've got last year's sales revenue totaled 505 150,000 current year. Excuse me. Current year sales revenue increased to 800,000, calculate the percentage change in sales revenue. Alright, So we're gonna use this formula and we are going to do the percentage change equals so percent change Equals um the change in X. So how do we calculate the change in X? It tells us that the the current year sales increased to 800. So this is our new value here. This is our original last year's value. So let's calculate this percentage change. Our new value being 800,000. I'm gonna put 800 K. Here for 1000 minus 550,000. 550 K. Divided by our original value which was 550 K. Alright, so we get 800 minus 5 50 is going to be 2 50 K. Over 5 50 K. And let's see what we get there. Our answer is going to be .4545. Alright, but is this answer in a decimal or percentage? It gives it to us as a decimal? Let's convert it to a percentage. So what we're going to take is our decimal and move it two places to the right, so move it two places to the right and it's gonna end up there. 45.45%. Cool. Alright, so in the next video, you guys are gonna practice this next one here.

The price of Clutch Pizza was originally $12. Clutch decides that everyone deserves more pizza and lowers the price to $10. Calculate the percentage change in the price of Clutch Pizza.

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