Using Percents in Everyday Life 1

Whether it is calculating how much will be taken off the price of a jacket when it is on sale for 40% off or trying to figure out how much in sales taxes will be added to our final purchase, percents are all around us. 

For example, in the latest Canadian Tire flyer, I saw an exercise bike that regularly sells for $1599.99 is being reduced by $960, for a sale price of $639.00.  How much would you save, as a percent of the original price?  To determine the percent off divide the discount amount ($960) by the original amount ($1600, rounding off the penny that doesn't really fool anyone), to give us a decimal.  $960 / $1600 = 0.6.  Multiply the decimal formed by 100 gives us the % amount.  0.6 X 100 = 60% off.

In the same flyer, I saw a shop-vac on sale for 25% off.  I can then determine its sale price.  First convert the percent into a decimal by dividing by 100.  25%  / 100 gives the decimal 0.25.  Take that decimal answer (0.25) and multiply it by the original price $169.99 to give the discount amount of $42.4975. which is rounded off to $42.50.  This discount amount of $42.50 is subtracted from the original amount of $169.99 to give a sale price of $127.49

Unfortunately, we then have to pay sales taxes, which are a percentage that is added to the purchase price.  In BC, there is a 7% Provincial Sales Tax which is combined with a 5% federal Goods and Services Tax for a total of 12% sales tax.  This 12% is calculated on the sale price and not the original amount.  To use the exercise bike, the 12% is calculated on the $639.00 (and not on the $1599.99).  Divide the 12% by 100 (12 / 100) to give the decimal 0.12, which is then multiplied by $639 (0.12 X $639.00).  This gives a tax amount of $76.68 which is added to the sale price ($639.00) to give a final price of $715.68

Try the following sales problems over the weekend.  In a flyer for The Bay, I saw a set of luggage advertised for 70% off.  If the suitcase was regularly $460, how much was the sale price and how much was the final price (including the 12% taxes).  Show your steps along the way.  I also saw some men's shoes, that were normally $110, on sale for a sale price of $64.99.  Calculate the final price of the shoes, including taxes.  Also show how much was taken off the original amount, as a percentage.

For each person who brings in these completed problems, a treat awaits on Monday morning.