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Xenia is really into social media. Hoping to increase the number of people following her on VidPicStar, she plans to test out different kinds of content – to learn what people really want to see.
First, she posts a really funny video she took at the zoo. Before the post, she had 240 followers. Her video post is a success! Now she has 312 followers.
The Percentage Change Formula
How successful was her post? Let’s use the percent change formula to calculate the increase in the number of her followers.
I'll write the formula down for you. The percent change is equal to the amount of change divided by the original value.
This will give you a decimal answer, so you will need to multiply the resulting decimal by one hundred to change it to a percent. Use common sense to decide if the percent of change is an increase or decrease.
Percentage Change Example 1
Let's put numbers into the formula. Remember, Xenia started out with 240 followers then increased to 312.
- 312 minus 240 divided by 240. The difference is seventy-two.
- Now divide by 240. The answer is three-tenths.
- To change to a percent, multiply three-tenths by one hundred.
The percent change is a thirty percent increase! Wow! A thirty percent increase is fantastic.
Percentage Change Example 2
Xenia wants even more followers. So she posts a picture of a tasty muffin. Will the muffin picture boost the number of followers? Let's see. Oh no! Quite the contrary. Her followers decreased to 265.
What is the percent change? Let's again write out the calculation using the percent change formula.
- First, find the difference between the two numbers. Three hundred twelve minus 265 then divide by the orginal value of 312. We get forty-seven.
- Now divide this by 312 and we get fifteen-hundredths.
- Fifteen-hundredths times one hundred is equal to fifteen percent. The number of Xenia's followers decreased by 15%.
Her followers really did not like that last posting, but then again, food pics are so passé. Xenia tries again. This time she posts a selfie. Maybe this glamorous pose will give her the boost she wants.