2. What does percentage mean? In mathematics, a percentage is a way of expressing a number as a fraction of 100 (per cent meaning "per hundred". It is often denoted using the percent sign, "%". For example, 45%) read as "forty five percent" is equal to 45 / 100, or 0.45.
3. Why are percentages necessary? It allows us to better visualize how much of a whole is being represented also is important for other things such as finance and interest rates. Shops advertise discounts on products. These discounts are percentages."Up to 50% off marked prices“ Financial institutions quote interest charged to the client on loans, or interest paid for money invested, as a percentage. "Housing Loans-4.95% p.a. for the first 12 months"Interest paid may be as Simple Interest or Compound Interest. Companies describe their success or failure as an increase or decrease in profit levels."C-Company profit down by 15% for the last financial year“ A salesperson may be given a commission as payment for selling goods. The commission can be a percentage of the sales made. "Position Vacant: 20% commission on all sales to the successful applicant.“ Articles such as antiques or jewelery may increase in value as time goes by-appreciation. Items such as equipment and machinery usually decrease in value-depreciation
4. When do we add a percentage? Weadd a percentagewhentheprice of anitem at a shop has tax. Anotherexample of addedpercentagesiswhen at a restaurant a certainamountispaid as a tip. A thirdsituationwouldbewhenanamount has increasedover a period of time: forexample , theprice of anitem, theminimumwageorthepopulation of a country fromoneyeartoanother.
5. When do we subtract a percentage? Thefirstsituationwouldbewhenanitem in a shop has a discount. Anotherinstancecouldbewhenwewanttoknowthe original price of anitemwhich has a taxonit.
6. How do wefindthepercentof anamount? Exercise: findthe 17% of $65 Steps: Changethepercentto decimal : 17% = 0.17 Multiplytheamountbythe decimal : 65x0.17 Theproductisthe 17% of 65. 65x0.17 = 11.05
7. Addingpercents Sometimeswehavetopaytaxes. Example: I am goingtobuy a sweater whose regular priceis $65. Butit has a tax of 17%. In this case, wehavetoaddthepercent. Sincewealreadyknowthat 17% of 65 is 11.05, theonlystep I havetofollownowistoaddthislastamounttothe original price: 65+11.05 = 76.05 Thelastamountisthe total price I havetopayforthecoat: $76.05
8. Applydiscountpercent Once youhavefoundthepercent of anamount, yousubtractitfromthe original price, ifthesituationcallsfor a discount. Example: I am goingtobuy a coatwhose regular priceis $65, buton sale it has a discount of 17%. Howmuch do I havetopay? Steps: I alreadyknowthat the17% of 65 is = 11.05 Now I subtractitfromthe original price: 65 – 11.05=53.95 Thedifference: $53.95 isthe final amount I am goingtopay.
