Math 6 And 7

MATHEMATICS 8 UNIT 6 PERCENTS RATIOS / FRACTIONS / DECIMALS PERCENT OF A NUMBER

PERCENT A PERCENT IS A FRACTION WITH A DENOMINATOR OF 100 Any fraction having a denominator of 100 is also an expression of the percent of the whole being discussed.

In such fractions, the numerator is known as the percent, or %

What would sixteen twenty-fifths be as a percent? x4

{16 x 4 = 64}

x4

It would be

RATIOS, FRACTIONS, DECIMALS, AND PERCENTS Fractional numbers can be expressed in several ways:

Fraction

Ratio

Decimal

Percent

We know the ratio will be

Remember? That line between the numerator and the denominator is a division line. That means this fraction is read “23 divided by 37.” Use your calculator for heaven’s sake! 23 divided by 37 = 0.6216216 or 0.62 (rounded)

0.62 is read 62

one hundredths or

From this, we know the percent is

Look at how the decimal point moves when changing a decimal to a fraction. It moves two to the right. When changing from a percent to a decimal, the decimal point moves two to the left.

PERCENT OF A NUMBER To find the percent of a number, write the percent as a decimal and then multiply by the number.

Example 2: Something Different What % of 44 is 11? Use the two given numbers to create a fraction. Another way to phrase the question is: What % is 11 out of 44? 11 divided by 44 = 0.25 0.25 = 25% Therefore, 11 is 25% of 44

MATHEMATICS 8 UNIT 7 DISCOUNT AND SALE PRICE PST AND GST COMMISSION AND INTEREST FINDING THE PERCENT

DISCOUNT AND SALE PRICE A discount is a certain percentage of a purchase price that is taken off an object in an attempt to get consumers to buy the product. A sale price is the price a consumer pays for a product after the discount has been subtracted.

A CD player has a regular price of $598.00. One day, the same CD player goes on sale with a discount of 25%. What is the new sale price? 1) Find out how much money the discount represents:

PST AND GST THESE ARE TWO TAXES FOUND IN MOST PARTS OF CANADA. THEY WILL EFFECT THE FINAL PRICE YOU PAY FOR PRODUCTS THAT HAVE THESE TAXES APPLIED TO THEM.

A mountain bike sells for $550.00. What will be the final purchase price after taxes? Note: The final price is the price you pay after any discounts have been subtracted and after all taxes have been added. In this case, the price of the bike + PST + GST

FINAL PRICE:

In Ontario, many items have both taxes placed on them. In this case, take the price of the item and multiply by the two taxes added together or, 15%

.

$550 x 0.15 = $82.50 550.00 + 82.50 = $632.50

COMMISSION COMMISSION IS A PERCENT OF THE COST OF SOME ITEM SOLD. MANY PEOPLE HAVE JOBS THAT PAY THEM A COMMISSION

A real estate agent makes 3% of the value of any home he/she sells. A home selling for $90,000.00 would pay the agent how much?

90,000.00 x 0.03 = 2,700.00 The agent would make $2,700.00 on the sale

INTEREST

Interest is the amount of money that is charged by a lender in order for someone else to use their money. Banks pay interest to customers based on the amount of money they have in the bank. Banks charge interest for customers borrowing money by taking out loans.

When I borrow money from the bank, I have to pay interest on top of the original amount that I borrowed. Interest rates can change daily and are often of different amounts. When I pay the bank back, I owe them the The amount of the original loan The amount of money the bank is charging me to lend the money

Let’s say I borrowed $20,000.00 at 8% interest to buy that splashy little sports model. How much will I have paid the bank after retiring the loan?

Principal = 20,000 Interest = 20,000 x 0.08 = 1,600

I owe the bank $21,600.00

Let’s say the term of my loan was for 48 months. That means that the bank will allow me to make 48 equal payments in order to pay off my loan. What will my monthly payments be?

This means that I must pay the bank $450 every month in order to keep the car. After 48 months, the car is mine.

100% OF A NUMBER 9% OF A NUMBER IS 72. WHAT IS THE NUMBER?

1) Use the 1% method. To find out what 1% of the number is, divide the number known by the percent. 8 is 1% of the number we’re looking for. To find 100% of the number, we multiply what 1% is by 100