Ws14 Percentages

Date:

______/______/ 2009

Marks

Worksheet 14: Percentages 1

Basic Jack and Jill want to buy some towels. A store displays the following signs.

Who is correct, Jack or Jill? Show working to explain your answer. Solution:

25 × 40% 100 = 10%

25% off Jan sale price =

Total sale off the original price = (60 + 10)% = 70% ∴ Jill is correct.

[Cedar Girl’s Sec School/2008] Ans: Jill © Victoria School Math Department

2

Basic Given that p is 20% of q, find the value of

p , expressing your answer as a fraction 4q

in its lowest terms.

Solution: p = 20% q 1 = q 5 1 q p 5 = 4q 4 q 1 = 20

[Anglican High School / 2008] 1 Ans: 20

3

Basic Each year, the Wild Wild Wet Theme Park invites its visitors to vote for their favourite thrill ride in the theme park. In 2006, there were 460 000 visitors and 91 000 of them voted. The number who voted in 2007 was 40% more than in 2006. If there were 390 000 visitors in 2007, calculate the number of visitors who did not vote in 2007.

Solution: Number of voters in 2007 =

140 × 91 000 100

= 127 400 Number of visitors who did not vote in 2007 = 390 000 – 127400

= 262 600

[Anglican High School / 2007] Ans: 262 600

© Victoria School Math Department

4

Basic (a)

An art dealer bought a painting for $8,400 and sold it for $11,088. Calculate his earnings as a percentage.

(b)

During a sale, the art dealer reduced the price of his paintings by 16%. Calculate the normal selling price of a painting which was priced at $21,000 during the sale.

Solution:

11 088 − 8400 × 100% 8400 = 32% 100 × $21 000 (b) Normal selling price = 84 = $25 000 (a) His earnings =

[Bukit Panjang Government High School / 2008] Ans: (a) 32% (b) $25 000

5

Basic The cost of a computer is $1200. (a)

At what price must a person sell it to make a profit of 20%?

(b)

At what price must a person advertise it if he is to give a 20% discount on the advertised price and still make a profit of 20% on the cost price?

Solution:

120 × $1 200 100 = $1 440

(a) Selling price =

100 × $1 440 80 = $1800

(b) Advertised price =

[Catholic High School / 2007] Ans: (a) $1 440 (b) $1 800

© Victoria School Math Department

6

Intermediate Anand wanted to sell a set of limited edition Transformers® toy figures which he bought for $11 000. The set of figures was finally sold during an auction to a buyer with a winning bid of $13 550. For the successful sale, the auctioneer receives 4% commission from the seller and 2% commission from the buyer. (A commission is money that you get from the sale of something.) (a) (b) (c)

How much profit did Anand make after paying commission to the auctioneer? Find, correct to 4 significant figures, the percentage of profit made in (a). How much did the auctioneer earn altogether?

Solution: (a)

4 × $13 550 100 = $542

Commission paid to auctioneer =

Profit made from the sale after commission = $13 550 − ( $11 000 + $542 ) = $2 008

2 008 ×100% 11 000 ≈ 18.25 %

(b)

Percentage profit Anand made from sale

=

(c)

Amount auctioneer earned from the seller and buyer  2+4  × $13 550  =   100  = $813

[Anglican High School / 2007] Ans: (a) $2008 (b) 18.25 % (c) $813

© Victoria School Math Department

7

Intermediate A sales promoter of an electronics shop is paid a commission of 5% for every computer set that he sells. The selling price of a computer set is $2 420. (a)

In a particular month, the sales promoter sold 15 computer sets. (i) Calculate the total commission received by the sales promoter. (ii) In that month, after paying the sales promoter his commission, the shop owner gets to keep 8% of the remaining amount as his earnings. Find the total amount the shop owner earned from this sale.

(b)

The selling price of a computer set is inclusive of a 10% GST. Find the price of a computer set without the inclusion of GST.

Solution: 5 × ( $2 420 ×15 ) 100 5 = × 36 300 100 = $1815

(ai) Total commission received =

8 × ( $36 300 − 1815 ) 100 = $2 758.80 100 (b) Price of a computer set before GST = × $2 420 110 = $2 200 (aii) Total amt earned =

[Cedar Girls’ Sec School / 2007] Ans: (ai) $1 815 (aii) $2 758.80 (b)$2 200

© Victoria School Math Department