Quick Questions
Spending Money
Scatterplots and Time Series
Probability
Mystery (Double Points!)
100
For credit cards, the bank requires a minimum monthly payment which is usually the greater of: (a) a certain fixed amount; (b) a specific percentage of the closing balance; (c) both (a) and (b); (d) none of the answers are correct; (e) Miss, we never learnt this.
(c) Both (a) and (b). The bank requires a minimum monthly payment which is usually the greater of a certain fixed amount or a specific percentage of the closing balance. See 3D (Credit Cards).
100
Angie plans to visit Tokyo on business. She changes A$800 into Japanese yen. For $1A, the buying price of Japan yen is 64.37 and the selling price is 63.13. How much does she receive in yen?
She will have 50,504 yen. See 3F (The exchange rate).
100
The following shows five students' marks on the English and History exams (E, H). (55, 72); (20, 37); (27, 53); (33, 74); (73, 73). Draw a (rough) scatterplot and say whether or not there appears to be a relationship.
In general, the greater the English mark, the greater the History mark. Therefore, there appears to be some relationship.
100
In a barrel there are 4 red marbles, 5 green marbles and 3 yellow marbles. One marble is drawn from a barrel. a) List the sample space b) How many elements are in the sample space? c) How many distinct elements are in the sample space?
a) S = {red, red, red, red, green, green, green, green, green, yellow, yellow, yellow} b) The sample space has 12 elements. c) The sample space has 3 distinct elements. See 12B (Sample Space).
100
New South Wales are playing Queensland in a State of Origin match. List the sample space for the possible outcomes of the match. Is each element of the sample space likely to occur? Explain your answer.
S = {NSW wins and QLD loses, QLD wins and NSW loses, they tie}. No these events are not equally likely to occur as both teams may not be of equal ability (i.e. QLD is better).
200
Both budget and expenses can be calculated: (a) weekly; (b) monthly; (c) quarterly; (d) all previous answers are correct.
(d) All previous answers are correct. Both budget and expenses can be calculated: weekly, monthly, quarterly or yearly. See 3B (Budgeting).
200
The account summary for a Telstra bill is as follows - Flexi-Plan balance = $8.40; Call charges = $116.51; Service and equipment = $42.45. What percentage of the total bill does the service charge represent?
The service charge represents 28.19% of the total bill. See 3D (Cost of services).
200
The horizontal axis represents which variable? The vertical axis represents which variable?
One variable, the independent variable, is on the horizontal axis and the other variable, the dependent variable, is on the vertical axis. See 11A (Scatterplots).
200
Give an example of an event which has a probability that could be described as: a) Even chance b) Impossible c) Probable
For example: a) Flipping a head on a fair coin. b) Rolling a 7 on a normal 6-sided die. c) It will be sunny today. See 12A (Informal Description of Chance).
200
After a discount of 15%, a jar of Kenya Gold coffee costs $10.15. Find the original price.
The original price is $11.94. See 3A (Discount).
300
Which of the following is the formula for gradient (m):(a) run/rise; (b) run x rise; (c) rise/run; (d) rise + run.
(c) rise/run = (change in y)/(change in x). To remember, alphabetise - rI is before rU. See 11B (Regression lines).
300
A store announces a 15% sale, so Jessie decides it is a good time to buy some new clothes. She buys a dress normally priced at $29, a jumper normally priced at $30, shoes normally priced at $26, a top normally priced at $18 and a necklace normally priced at $16. What is the total cost of the clothes and the amount that she paid after the discount was applied?
Without the discount, the clothes would cost $119. With the discount, the clothes would cost $101.15. See 3A (Discount).
300
A taxi company adjusts its meters so that the fare is charged according to the following equation: F = 1.2d + 3 where F is the fare in dollars and d is the distance travelled in kilometers. Find the fare charged for a distance of 12 kilometers. Find the distance that could be covered on a fare of $27.
For 12 kilometers the company would charge $17.20. For a fare of $27, you could travel 20km. See 11B (Regression lines).
300
(Requires all three parts to be correct for points): Four coins are tossed into the air. a) Draw a tree diagram for this event. b) Use your tree to list the sample space. c) How many elements have an equal number of Heads and Tails?
a) Check with me. b) S = {HHHH, HHHT, HHTH, HHTT, HTHH, HTHT, HTTH, HTTT, THHH, THHT, THTH, THTT, TTHH, TTHT, TTTH, TTTT} (don't forget the curly brackets!) c) 6 See 12C (Tree Diagrams).
300
By selling a collection of coins for $177, Igor makes a profit of 18%. What was the original cost of the collection?
The original cost of the collection was $150. See 3B (Profit and loss).
400
What is the formula for percentage discount? (a) (Selling price - Cost price) x 100% (b) (Discount/Orignial Price) x 100%;(c) Original price - Sale price; (d) Original price - percentage of the original price
(b) (Discount/Original Price) x 100% See 3A (Discount).
400
Look at the following budget for a nonprofit organisation: Government pays them $4200, they have annual membership fees of $25 per person, and gain profit from previous events. The auction raised $400, the food stalls $230 and the two concerts about $1800 each. They estimate 650 people will renew membership. They expect to spend $500 each month on rent, $240 per quarter on the newspaper, and $17,810 for other costs. The rest will be spent on charity. How much is leftover for charity?
The amount left for charity is $600. (The total income is $25,370. The total expenditure is $24,770.) See 3C (Budgeting).
400
There are four basic types of trend. Name 2 of them.
Secular (increasing or decreasing steadily); Seasonal (varying from season to season); Cyclic (similar to seasonal but not tied to a calendar cycle); Random (varying from external causes happening at random. See 11C (Time Series and Trend Lines).
400
State whether the statement is true or false and give a reason for your answer: A book is opened on any page and a pin is stuck in the page. The letter closest to the pin is then noted. Each letter of the alphabet has an equal chance of being selected.
False. See 12D (Equally likely outcomes). On a page of writing, each letter of the alphabet does not occur equally often.
400
A family pays $101.00 each month for calls, 2.50 each month to rent the telephone handset, $11.65 each month to rent the telephone line and $18.00 for their family plan. If they buy a telephone valued at $89 and hence stop renting one from Telstra, in how many months will the savings from not paying rental cover the cost of the new phone? (Round to the next month)
36 months. See 3D (Cost of services).
500
When you exchange A$ for other currencies the bank sells you the other currency. Therefore: (a) multiply by the selling price; (b) divide by the selling price; (c) multiply by the buying price; (d) divide by the buying price.
(a) multiply by the selling price. When you exchange A$ for other currencies the bank sells you the other currency. Therefore multiply by the selling price. See 13F (The Exchange Rate).
500
ANZ Bank requires the minimum payment off credit card balances to be the greatest of (a) 2.5% of the closing balance (rounded down to the nearest dollar), or (b) $25. What is the minimum payment on the balance of $785?
$25 is the minimum payment. See 3E (Credit cards).
500
A football match pie seller finds that the number of pies sold is related to the temperature of the day, as modelled by N = 870 - 23t, where N is the number of pies sold and t is the temperature of the day. a) Find the number of pies sold if the temperature was 5 degrees. b) Find the likely temperature if 400 pies were sold?
a) 755 pies would be sold. N = 870 - 23x5 = 870 - 115 = 755. b) 20 degrees C. 400 = 860 - 23t. Rearrange to get -460 = -23t. t = 20. See 11B (Regression Lines).
500
Home telephone numbers in Australia have eight digits. A certain mobile network has numbers beginning with 015 or 018 followed by six digits. How many numbers can this network have?
2,000,000 numbers. See 12E (Fundamental Counting Principle). Each number is either 015XXXXXX or 018XXXXXX. Each X can be one of ten numbers. Therefore do 10x10x10x10x10x10 (10^6) = 1,000,000. This is the result for both 015 and 018, so add them together to get 2,000,000.
500
Mark had a collection of 5 Hilltop Hoods CDs, which he purchased over a period of time at $29.95 each. A friend offered to pay $70 for the whole set. Find the loss in dollars and express it as a percentage of the cost price.
Mark would lose $79.95, which is 53.26% of the cost price. See 3B (Profit and loss).
M
e
n
u