[Mathematic Form 1] Percentages

Percentages

• A percentage is a fraction with 100 as the denominator
• It is represented by the symbol %

Eg: 15/100 is 15%

The percentage of increase or decrease

Percentage increase = (Amount increase / Original value) x 100%

Percentage decrease = (Amount decrease / Original value) x 100%

Eg:

a) Find the decrease percentage when RM250 is decreased by RM55

Amount decrease = RM55

Percentage decrease = (RM55 / RM250) x 100% = 22%

b) In February, Aiman sold 560 durians. In March, the number of durians that he sold increased by 15%. How many durians did he sell in March?

Amount increase = Percentage increase x Original value

Amount increase = 15% x 560 = (15/100) x 560 = 84

New value = Original value + Amount increase

New value = 560 + 84 = 644

In March, he sold 644 durians.

[Mathematic Form 1] Commission

Commission is the amount of money paid to an agent for his or her effort in selling a product or service.

Commission = Percentage commission (commission rate) x Amount of sales

Eg:
1. A book salesman will receive a commission of 15% on the sale of books. If his sales of book reach RM2,500, find the commission the salesman will get.

Commission = Percentage commission (commission rate) x Amount of sales
Commission = 15% x RM2,500
Commission = (15/100) x RM2,500 = RM375

The salesman will get RM375 as commission.

2. Yazid gets a commission of RM15 for the sale of shoes at RM500. Calculate the percentage of commission given to him.

Percentage of commission = (Commission / Amount of sales) x 100%
Percentage of commission = (RM15 / RM500) x 100% = 3%

The percentage of commission given to Yazid is 3%.

3. Hisham will be given a commission of 5% for every notebook he sells. If he sells 3 notebooks which cost RM3,500 each, how much commission will he receive?

Percentage of commission = 5%
Amount of sales = RM3,500 x 3 = RM10,500

Commission = Percentage commission (commission rate) x Amount of sales
Commission = 5% x RM10,500
Commission = (5 / 100) x RM10,500 = 0.05 x RM10,500 = RM525

Hisham will get RM525 as commission.

4. Rahman was paid a commission of RM4,000 for selling a house. If the price of the house was RM250,000, what was the commission rate?

Commission = RM4,000
Amount of sales = RM250,000
Percentage commission (commission rate) = (Commission / Amount of sales) x 100%
Commission rate = (RM4,000 /RM 250,000) x 100%
Commission rate = 0.016 x 100% = 1.6%

The commission rate is 1.6%.

5. A salesman receives RM1,500 as commission for the sale of books. If the commission is 25%, find the amount of sales that the salesman has obtained.

Commission = RM1,500
Percentage commission = 25%

Percentage commission (commission rate) = (Commission / Amount of sales) x 100%
Amount of sales = (Commission / Percentage commission) x 100%
Amount of sales = (RM1,500 / 25%) x 100%
Amount of sales = RM6,000

The amount of sales that the salesman has obtained is RM6,000.

[Mathematic Form 1] Discount

A discount is a reduction in the original selling price.

Discount = Original selling price - New selling price

Percentage discount = (Discount / Original selling price) x 100%

Eg:
a) A shirt was sold at RM45 during sale. If the original price of the shirt was RM60, calculate the discount and the percentage discount.

Discount = Original selling price - New selling price
= RM60 - RM45
= RM15

Percentage discount = (Discount / Original selling price) x 100%
= (RM15 / RM60) x 100%
= 25%

Hence, the percentage discount is 25%

b) During a sale, a handbag is sold at a discount of 30%. What is the new selling price if the original price is RM80?

Percentage discount = (Discount / Original selling price) x 100%
30% = (Discount / RM80) x 100%
Discount = (Percentage discount / 100%) x Original selling price
Discount = (30% / 100%) x RM80 = 0.3 x RM80 = RM24

Discount = Original selling price - New selling price
New selling price = Original selling price - Discount = RM80 - RM24
New selling price = RM56

c) A dress with an original price of RM150 was sold at RM90 during a sale. What is the percentage discount offered?

Original selling price = RM150
New selling price = RM90
Discount = Original selling price - New selling price
Discount = RM150 - RM90 = RM60

Discount = (Percentage of discount / 100%) x Original selling price
Percentage discount = (Discount / Original selling price) x 100%
Percentage discount = (RM60 / RM150) x 100% = 0.4 x 100%
Percentage discount = 40%

Hence, the percentage discount offered = 40%

d) Nina saved RM105 when she bought a dining table at a discount of 15%. Calculate the original price of the table.

Discount = RM105
Percentage discount = 15%

Percentage discount = (Discount / Original selling price) x 100%
Original selling price = (Discount / Percentage discount) x 100%
Original selling price = (RM105 / 15%) x 100% = 7 x 100 = RM700

Hence, the original price of the table is RM700.

[Mathematic Form 1] Simple Interest & Dividend

Simple interest is an additional amount of money given

• by the bank when you save money
• to the bank when you borrow money

Simple Interest = Interest Rate x Principal x Time

Eg:
1. Ahmad deposited RM3,000 in a bank for 3 years at an interest rate of 3.5% per annum. How much interest will Ahmad receive at the end of the period?

Simple Interest = Interest Rate x Principal x Time
= 3.5% x RM3,000 x 3
= (3.5/100) x RM3,000 x 3
= RM315

Hence, Ahmad will receive RM315 as interest at the end of the period.

2. Mak Limah borrowed RM50,000 from a bank. She has paid RM3,000 as simple interest for 3 years. Calculate the interest rate per annum paid by Mak Limah.

Interest Rate = [ Simple Interest / (Principal x Time) ] x 100%
= [ RM3,000 / (RM50,000 x 3) ] x 100%
= 2%

Hence, the interest rate paid by Mak Limah is at 2% per annum.

Dividend

Dividend: profit that is paid to a company's shareholders for their investment in the company.

Dividend = Rate of Dividend x Investment

Eg:
1. Danial bought RM28,000 worth of shares in a company and was given a dividend of 13%. Calculate the amount of dividend received by Danial.

Dividend = Rate of Dividend x Investment
= 13% x RM28,000
= (13/100) x RM28,000
= RM3,640

Danial will receive RM3,640 as dividend.

2. Anita bought 8,000 units of share at RM0.50 per unit. At the end of the year, she was paid a dividend of RM220. What is the rate of dividend given to her?

Investment = 8,000 x RM0.50 = RM4,000
Rate of Dividend = (RM220/RM4,000) x 100% = 5.5%

The rate of dividend given to Anita is 5.5%.