Presentation on theme: "Percentages By Harris, Draven, And Gaige. What is a percentage and how do I find it? A percentage is a fraction of a whole number. To find the percentage."— Presentation transcript:
What is a percentage and how do I find it? A percentage is a fraction of a whole number. To find the percentage of a whole number you divide the number you do the fraction of that number divided by the whole. I.E.- If the total number is 35 and I need to find what percentage of 7 is in 35. so I will divide 7 by 35 and get.20. I will move the decimal over twice and get 20%. This means that 7 is 20% of 35.
Application of percentages The application of percentages is using proportions to solve real world problems involving percentages. To do this you set up a proportion and cross multiply and you use the variable for taxes, tips, and discounts.
Example 1: App. Of percent's n/75 x 15/100 cross multiply 100n/100 x 1,125/100 N=11.25
Simple Intrest Simple interest is a quick method of finding interest on investments and is found by multiplying interest (I) by amount invested (P) by amount of time invested (T) (in this case, years)
Example 2: Simple Interest R= 0.045 x P=500 x T=3 =I? I=67.5
Percent of Increase Percent of increase is the measurement of how much something gains value. To find percent of increase you take new amount- original amount/ original amount.
Example 3: Percent of Increase Population of a city in 1990: 513,117 Population of same city in 2000: 583,845 583,845 – 513,117 513,117 513,117=0.13783…
Percent of Decrease Percent of decrease is the measurement of how much something loses value. To find percent of decrease original amount- new amount/ original amount.
Example 4: Percent of Decrease Ave. score of a team season 1: 74.9 Ave score season 2: 61.6 74.9 – 61.6 74.9 =0.17757