Which expression is equal to `6^3 xx 36^2`?
- `6 xx 3 xx 36 xx 2`
- `6 xx 6 xx 6 xx 6 xx 6`
- `6 xx 6 xx 6 xx 36 xx 6`
- `6 xx 6 xx 6 xx 6 xx 6 xx 6 xx 6`
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Which expression is equal to `6^3 xx 36^2`?
`D`
| `6^3 xx 36^2` | `= (6xx6xx6) xx (6xx6)^2` |
| `= (6xx6xx6) xx (6xx6) xx (6 xx6)` | |
| `=6 xx 6 xx 6 xx 6 xx 6 xx 6 xx 6` |
`=>D`
`7 xx 2^3 =`
`C`
| `7 xx 2^3` | `= 7 xx 2 xx 2 xx 2` |
| `= 56` |
`=>C`
`30^2` is equal to which of the following?
`B`
`30^2 = 900`
`3^2 xx 2 xx 5 xx 2 xx 5`
`= 3^2 xx 10 xx 10`
`= 900`
`=>B`
Which of the following is equal to 32?
`=>A`
| `2^3 xx 2^2` | `= 8 xx 4` |
| `= 32` |
`=>A`
Expand and simplify the expression
`13-3(x-4)` (2 marks)
`25-3x`
| `13-3(x-4)` | `=13-3x+12` | |
| `=25-3x` |
Expand and simplify the expression
`3a(4a-5)-2(a-3)` (2 marks)
`12a^2-17a+6`
| `3a(4a-5)-2(a-3)` | `=12a^2-15a-2a+6` | |
| `=12a^2-17a+6` |
Expand the expression `-2(5x^2-3x-4)` (2 marks)
`-10x^2+6x+8`
`-2(5x^2-3x-4)=-10x^2+6x+8`
Expand the expression `3(2y^2-3y+1)` (2 marks)
`6y^2-9y+3`
`3(2y^2-3y+1)=6y^2-9y+3`
Expand and simplify the expression `4a(a-3)-5(6-a)` (2 marks)
`4a^2-7a-30`
| `4a(a-3)-5(6-a)` | `=4a^2-12a-30+5a` | |
| `=4a^2-7a-30` |
Expand and simplify the expression `3x(x-2)+4(x-5)` (2 marks)
`3x^2-2x-20`
| `3x(x-2)+4(x-5)` | `=3x^2-6x+4x-20` | |
| `=3x^2-2x-20` |
Which of the following is always equal to `a-b`?
`D`
`a-b = -b + a`
`=>D`
Which expression is equivalent to `4x^2-12x + x^3?`
`D`
`x (4x-12 + x^2)`
`= 4x^2-12x + x^3`
`=>D`
What expression is equivalent to `-(y-6)`?
`D`
`-(y-6) = -y-(-6)=-y + 6`
`=>D`
Which expression is equal to `4x-8 + 3x + 2`?
`B`
`4x-8 + 3x + 2=7x-6`
`=>B`
Which expression is equivalent to `12x + 24`?
`A`
| `3 (4x + 8)` | `= 3 xx 4x + 3 xx 8` |
| `= 12x + 24` |
`=>A`
Which expression is equivalent to `5-6t`?
`D`
`-6t+5`
`=>D`
Which one of the following expressions is equivalent to `4 (3m-1)`?
`C`
`4 (3m-1)`
`= (4 xx 3m)-(4 xx 1)`
`= 12m-4`
`=>C`
The expression `3x + 7 + 8x + 11` can also be written as
`B`
`3x + 7 + 8x + 11 = 11x + 18`
`=>B`
Simplify the expression `(9h)/2 -: (h)/3` (2 marks)
`(27)/2`
| `(9h)/2 -: (h)/3` | `=(9h)/2 xx 3/(h)` | |
| `=(9h xx 3)/(2 xx h)` | ||
| `=(27)/2` |
Simplify the expression `(13x)/15 -: (2x)/5` (2 marks)
`(13)/6`
| `(13x)/15 -: (2x)/5` | `=(13x)/15 xx 5/(2x)` | |
| `=(13x xx 5)/(15 xx 2x)` | ||
| `=(13)/6` |
Simplify the expression `(3a)/4 -: (7a)/2` (2 marks)
`(3)/14`
| `(3a)/4 -: (7a)/2` | `=(3a)/4 xx 2/(7a)` | |
| `=(3a xx 2)/(4 xx 7a)` | ||
| `=(3)/14` |
Simplify the expression `(3p)/4 xx (8p)/9` (2 marks)
`(2p^2)/3`
| `(3p)/4 xx (8p)/9` | `=(3p xx 8p)/(4 xx 9)` | |
| `=(p xx 2p)/3` | ||
| `=(2p^2)/3` |
Simplify the expression `(2a)/7 xx (14a)/3` (2 marks)
`(4a^2)/3`
| `(2a)/7 xx (14a)/3` | `=(2a xx 14a)/(7 xx 3)` | |
| `=(2a xx 2a)/3` | ||
| `=(4a^2)/3` |
Simplify the expression `(5)/6 xx c/4` (2 marks)
`(5c)/24`
| `(5)/6 xx c/4` | `=(5 xx c)/(6 xx 4)` | |
| `=(5c)/24` |
Simplify the expression `(5x)/9-x/6` (2 marks)
`(7x)/18`
| `(5x)/9-x/6` | `=(10x)/18-(3x)/18` | |
| `=(7x)/18` |
Simplify the expression `b/2-b/3` (2 marks)
`b/6`
| `b/2-b/3` | `=(3b)/6-(2b)/6` | |
| `=b/6` |
Simplify the expression `(4x)/5-(x)/3` (2 marks)
`(7x)/15`
| `(4x)/5-(x)/3` | `=(12x)/15-(5x)/15` | |
| `=(7x)/15` |
Simplify the expression `(3t)/5-(t)/2` (2 marks)
`(t)/10`
| `(3t)/5-(t)/2` | `=(6t)/10-(5t)/10` | |
| `=(t)/10` |
Simplify the expression `(3a)/5+(a)/4` (2 marks)
`(17a)/20`
| `(3a)/5+(a)/4` | `=(12a)/20+(5a)/20` | |
| `=(17a)/20` |
Simplify the expression `x/4+(2x)/3` (2 marks)
`(11x)/12`
| `x/4+(2x)/3` | `=(3x)/12+(8x)/12` | |
| `=(11x)/12` |
Simplify the expression `p/2+p/3` (2 marks)
`(5p)/6`
| `p/2+p/3` | `=(3p)/6+(2p)/6` | |
| `=(5p)/6` |
The table shows the income tax rates for the 2022-23 financial year.
\begin{array} {|l|l|}
\hline
\rule{0pt}{2.5ex}\textit{ Taxable income}\rule[-1ex]{0pt}{0pt} & \textit{ Tax payable}\\
\hline
\rule{0pt}{2.5ex}\text{\$0 – \$18 200}\rule[-1ex]{0pt}{0pt} & \text{Nil}\\
\hline
\rule{0pt}{2.5ex}\text{\$18 201 – \$45 000}\rule[-1ex]{0pt}{0pt} & \text{19 cents for each \$1 over \$18 200}\\
\hline
\rule{0pt}{2.5ex}\text{\$45 001 – \$120 000}\rule[-1ex]{0pt}{0pt} & \text{\$5092 plus 32.5 cents for each \$1 over \$45 000}\\
\hline
\rule{0pt}{2.5ex}\text{\$120 001 – \$180 000}\rule[-1ex]{0pt}{0pt} & \text{\$29 467 plus 37 cents for each \$1 over \$120 000}\\
\hline
\rule{0pt}{2.5ex}\text{\$180 001 and over}\rule[-1ex]{0pt}{0pt} & \text{\$51 667 plus 45 cents for each \$1 over \$180 000}\\
\hline
\end{array}
Boonie is a professional cricketer and has a gross income of $145 000. During the financial year, he has allowable tax deductions of $1300 for cricket bats and pads.
What is Boonie's total amount of tax payable for the financial year? (3 marks)
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`$38\ 236`
`text(Taxable income)\ =145\ 000-1300=$143\ 700`
`text{Tax payable}`
`= 29\ 467 + 0.37 (143\ 700-120\ 000)`
`= 29\ 467 + 8769`
`= $38\ 236`
\begin{array} {|l|l|}
\hline
\rule{0pt}{2.5ex}\textit{ Taxable income}\rule[-1ex]{0pt}{0pt} & \textit{ Tax payable}\\
\hline
\rule{0pt}{2.5ex}\text{\$0 – \$18 200}\rule[-1ex]{0pt}{0pt} & \text{Nil}\\
\hline
\rule{0pt}{2.5ex}\text{\$18 201 – \$45 000}\rule[-1ex]{0pt}{0pt} & \text{19 cents for each \$1 over \$18 200}\\
\hline
\rule{0pt}{2.5ex}\text{\$45 001 – \$120 000}\rule[-1ex]{0pt}{0pt} & \text{\$5092 plus 32.5 cents for each \$1 over \$45 000}\\
\hline
\rule{0pt}{2.5ex}\text{\$120 001 – \$180 000}\rule[-1ex]{0pt}{0pt} & \text{\$29 467 plus 37 cents for each \$1 over \$120 000}\\
\hline
\rule{0pt}{2.5ex}\text{\$180 001 and over}\rule[-1ex]{0pt}{0pt} & \text{\$51 667 plus 45 cents for each \$1 over \$180 000}\\
\hline
\end{array}
Using the tax table, what is the tax payable on $47 580?
`B`
`text(Tax Payable)`
`= 5092 + 0.325 (47\ 580-45\ 000)`
`= 5092 + 838.50`
`= 5930.50`
`=> B`
George makes a single deposit of $9000 into an account that pays simple interest.
After 4 years, George's account has a balance of $10 350.
What simple interest rate did George receive on his investment? (2 marks)
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`3.75text(%)`
| `text(Interest earned)` | `= 10\ 350-9000` |
| `= $1350` |
`text(Using)\ \ I = Prn,`
| `1350` | `= 9000 xx r xx 4` |
| `:. r` | `= 1350/(4 xx 9000)` |
| `= 0.0375` | |
| `= 3.75text(%)` |
$6000 is invested in an account that earns simple interest at the rate of 3.5% per annum.
The total interest earned in the first four years is
`D`
`P = 6000,\ \ r = 3.5text(%),\ \ n = 4`
| `I` | `= Prn` |
| `= 6000 xx 3.5/100 xx 4` | |
| `= 840` |
`=> D`
Pamela deposits $2000 into a savings account which earns simple interest at the rate of 2.5% per annum.
No deposits or withdrawals are made from this account.
After 2 years, how much is in Pamela's savings account? (2 marks)
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`$2100`
| `text(Interest earned)` | `= Prn` |
| `= 2000 xx 2.5/100 xx 2` | |
| `= $100` |
| `:.\ text{Account balance}` | `= 2000 + 100` |
| `= $2100` |
Dante deposits $5000 into a savings account which earns simple interest.
No deposits or withdrawals are made from this account.
After 4 years, Dante notices there is $5600 in the account.
What is the annual rate of interest for the account? (2 marks)
--- 4 WORK AREA LINES (style=lined) ---
`3text(%)`
| `text(Interest per year)` | `= (5600-5000)÷4` |
| `= 600 ÷ 4` | |
| `= $150` |
| `:.\ text{Interest rate (p.a.)}` | `= 150/5000 xx 100` |
| `= 3 text(%)` |
Mr. Soros put $500 into a simple interest account for a year.
He did not take any money out or add any money to the account.
At the end of the year he had $530 in the account.
What was the annual percentage interest rate? (2 marks)
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`text(6%)`
| `text(Interest earned)` | `= 530-500` |
| `= $30` |
`:.\ text{Interest rate (annual)}`
`= 30/500`
`= 0.06`
`= 6text(%)`
Cassie opens a savings account and deposits $900 into it.
She makes no more deposits and earns simple interest on her original deposit at 3.5% each year.
How much interest will Cassie earn after 4 years? (2 marks)
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`$126`
| `text(Interest earned)` | `=Prn` |
| `= 900 xx 3.5/100 xx 4` | |
| `= $126` |
On a weekend, Abbey works 8 hours at her normal pay rate and 12 hours at time and a half of her normal pay.
Abbey was paid $707.20 in total for this work.
What is her normal pay rate per hour? (2 marks)
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`$27.20\ text(per hour)`
`text(Total normal hours)`
`= 8 + 1.5 xx 12`
`= 26`
`:.\ text(Abbey’s normal pay rate)`
`= 707.20/26`
`= $ 27.20\ text(per hour.)`
John, Olivia and Louis are picking grapes to earn money.
Their pay is based on the number of tonnes of grapes they pick.
| Tonnes picked | |
| John | 4 |
| Olivia | 3 |
| Louis | 1 |
Their total pay is $640.
How much does Olivia earn? (2 marks)
--- 4 WORK AREA LINES (style=lined) ---
`$240`
`text(Payment per tonne)`
`= 640/8`
`= $80`
| `:.\ text(Olivia earns)` | `= 3 xx 80` |
| `= $240` |
David has a job selling mobile phone plans. His weekly salary, `W` dollars, is calculated using the rule below:
`W = 300 + 0.05 P`
where `P` is the total value in dollars of the mobile phone plans he sells that week.
David sold $32 000 worth of mobile phone plans in a given week.
What was David's salary in the week?
`C`
| `W` | `= 300 + 0.05 xx 32\ 000` |
| `= 300 + 1600` | |
| `= 1900` |
`=>C`
Bella is an electrician.
She charges $150 to attend a job and then a fixed price for each minute she spends on the job.
The graph below shows Bella's charge based on the number of minutes she spends at the job.
How much will Bella charge for a job that takes 60 minutes? (2 marks)
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`$330`
`text(Charge to attend = $150)`
`text(From the graph,)`
`=>\ text(50 minute job costs $300)`
| `:.\ text(C)text(ost per minute)` | `= (300-150)/50 = $3` |
`:.\ text(C)text(ost of 60 minute job)`
`= 150 + 60 xx 3`
`= $330`
Olivia earned $17.24 per hour working at a pizza store.
This week she worked for `8 1/4` hours.
She used the money she earned this week to buy concert tickets for herself and her friends.
Each concert ticket cost $14.15.
Calculate the maximum number of concert tickets Olivia could have bought? (2 marks)
--- 4 WORK AREA LINES (style=lined) ---
`10`
| `text(Money earned)` | `= 8 1/4 xx 17.24` |
| `= $142.23` |
| `:.\ text(Maximum tickets)` | `= 142.23/14.15` |
| `= 10.05…` | |
| `= 10` |
Given the formula `C = (A(y + 1))/24`, calculate the value of `y` when `C = 120` and `A = 500`. (3 marks)
--- 6 WORK AREA LINES (style=lined) ---
`4.76`
`text(Make)\ \ y\ \ text(the subject:)`
| `C` | `= (A(y + 1))/24` |
| `24C` | `= A(y + 1)` |
| `y + 1` | `= (24C)/A` |
| `y` | `= (24C)/A-1` |
| `= (24 xx 120)/500-1` | |
| `= 4.76` |
`C`
`text{Scale factor}\ =3/2 =1.5`
`:.\ x = 1.5 xx 12 = 18`
`text{Alternate solution}`
`text{Using sides of similar figures in the same ratio:}`
| `x/12` | `=3/2` | |
| `x` | `=12 xx (3/2)` | |
| `x` | `=18` |
`=> C`
A dam is in the shape of a triangular prism which is 50 m long, as shown.
Both ends of the dam, `A B C` and `D E F`, are isosceles triangles with equal sides of length 25 metres. The included angles `B A C` and `E D F` are each `150^@`.
Calculate the number of litres of water the dam will hold when full. (4 marks)
--- 8 WORK AREA LINES (style=lined) ---
`7\ 812\ 500\ text{L}`
`V=Ah`
`text{Use sine rule to find}\ A:`
| `A` | `=1/2 ab\ sinC` | |
| `=1/2 xx 25 xx 25 xx sin150^@` | ||
| `=156.25\ text{m}^2` |
| `:.V` | `=156.25 xx 50` | |
| `=7812.5\ text{m}^3` |
`text{S}text{ince 1 m³ = 1000 litres:}`
| `text{Dam capacity}` | `=7812.5 xx 1000` | |
| `=7\ 812\ 500\ text{L}` |
A real estate agent's commission for selling houses is 2% for the first $800 000 of the sale price and 1.5% for any amount over $800 000.
Calculate the commission earned in selling a house for $1 500 000. (2 marks)
`$26\ 500`
| `text{Commission}` | `=800\ 000 xx 2text{%} + (1\ 500\ 000-800\ 000) xx 1.5text{%}` | |
| `=800\ 000 xx 0.02 + 700\ 000 xx 0.015` | ||
| `=16\ 000 + 10\ 500` | ||
| `=$26\ 500` |
Tian is paid $20.45 per hour, as well as a meal allowance of $16.20 per day.
What are Tian's total earnings if she works 9 hours per day for 5 days?
`C`
| `text{Earnings (5 days)}` | `=5 xx [(9 xx 20.45) + 16.20]` | |
| `=5 xx 200.25` | ||
| `=$1001.25` |
`=>C`
Solve `x+(x-1)/2 = 9`. (2 marks)
`19/3`
| `x+(x-1)/2` | `=9` | |
| `2x + x-1` | `=18` | |
| `3x` | `=19` | |
| `x` | `=19/3` |
Suppose `a=b/7`, where `b=22.`
What is the value of `a`, correct to three significant figures?
`A`
`a=b/7=22/7=3.1428…`
`3.1428 = 3.14\ text{(to 3 sig fig)}`
`=> A`
\(38 \ \ 25 \ \ 38 \ \ 46 \ \ 55 \ \ 68 \ \ 72 \ \ 55 \ \ 36 \ \ 38\)
--- 4 WORK AREA LINES (style=lined) ---
--- 5 WORK AREA LINES (style=lined) ---
a. \(1\)
b. \(\text{Standard deviation is a measure of how much the}\)
\(\text{ages of individuals differ from the mean age of the group.}\)
\(\Rightarrow\ \text{Standard deviation of Wednesday’s group would be}\)
\(\text{less as the mean is 70 and everyone’s age is 70.}\)
a. \(\text{Reorder ages in ascending order:}\)
\(25, 36, 38, 38, 38, 46, 55 , 55, 68, 72\)
\(\text{Median} = \dfrac{\text{5th + 6th}}{2} = \dfrac{38 + 46}{2} = 42\)
\(\therefore\ \text{People with age between 42 − 47.1 = 1}\)
b. \(\text{Standard deviation is a measure of how much the}\)
\(\text{ages of individuals differ from the mean age of the group.}\)
\(\Rightarrow\ \text{Standard deviation of Wednesday’s group would be}\)
\(\text{less as the mean is 70 and everyone’s age is 70.}\)
A composite solid consists of a triangular prism which fits exactly on top of a cube, as shown.
Find the surface area of the composite solid. (3 marks)
--- 6 WORK AREA LINES (style=lined) ---
`424 \ text{cm}^2`
`text{S.A. of 1 face of cube} = 8 xx 8 = 64 \ text{cm}^2`
`text{Height of triangle} = 11 – 8 = 3 \ text{cm}`
| `therefore \ text{S.A. (triangular prism)}` | `= 2 xx ( frac{1}{2} xx 8 xx 3 ) + 2 xx (5 xx 8)` |
| `= 24 + 80` | |
| `= 104 \ text{cm}^2` |
| `therefore \ text{Total S.A.}` | `= 5 xx 64 + 104` |
| `= 424 \ text{cm}^2` |
The table shows the income tax rates for the 2019 – 2020 financial year.
\begin{array} {|l|l|}
\hline
\rule{0pt}{2.5ex}\textit{ Taxable income}\rule[-1ex]{0pt}{0pt} & \textit{ Tax payable}\\
\hline
\rule{0pt}{2.5ex}\text{\$0 – \$18 200}\rule[-1ex]{0pt}{0pt} & \text{Nil}\\
\hline
\rule{0pt}{2.5ex}\text{\$18 201 – \$37 000}\rule[-1ex]{0pt}{0pt} & \text{19 cents for each \$1 over \$18 200}\\
\hline
\rule{0pt}{2.5ex}\text{\$37 001 – \$90 000}\rule[-1ex]{0pt}{0pt} & \text{\$3572 plus 32.5 cents for each \$1 over \$37 000}\\
\hline
\rule{0pt}{2.5ex}\text{\$90 001 – \$180 000}\rule[-1ex]{0pt}{0pt} & \text{\$20 797 plus 37 cents for each \$1 over \$90 000}\\
\hline
\rule{0pt}{2.5ex}\text{\$180 001 and over}\rule[-1ex]{0pt}{0pt} & \text{\$54 097 plus 45 cents for each \$1 over \$180 000}\\
\hline
\end{array}
For the 2019 – 2020 financial year, Wally had a taxable income of $122 680. During the year, he paid $3000 per month in Pay As You Go (PAYG) tax.
Calculate Wally's tax refund, ignoring the Medicare levy. (3 marks)
--- 6 WORK AREA LINES (style=lined) ---
`$3111.40`
| `text(Tax paid)` | `=12 xx 3000` |
| `=$36\ 000` |
`text(Tax payable on $122 680)`
`=20\ 797 + 0.37(122\ 680-90\ 000)`
`=20\ 797 + 0.37(32\ 680)`
`=$32\ 888.60`
| `:.\ text(Tax refund)` | `=36\ 000-32\ 888.60` | |
| `=$3111.40` |
Consider the triangle shown.
--- 4 WORK AREA LINES (style=lined) ---
--- 4 WORK AREA LINES (style=lined) ---
| a. | `tan theta` | `= frac{8}{10}` |
| `theta` | `= tan ^(-1) frac{8}{10}` | |
| `= 38.659…` | ||
| `= 39^@ \ text{(nearest degree)}` |
b. `text{Using Pythagoras:}`
| `x` | `= sqrt{8^2 + 10^2}` |
| `= 12.806…` | |
| `= 12.8 \ \ text{(to 1 d.p.)}` |
A plant stem is measured to be 16.0 cm, correct to one decimal place.
What is the percentage error in this measurement?
`A`
`text{Absolute error} = 1/2 xx \text{precision} = 1/2 xx 0.1 = 0.05\ text{cm}`
| `% text(error)` | `= frac(0.05)(16.0) xx 100` |
| `= 0.3125%` |
`=> \ A`
A bowl of fruit contains 17 apples of which 9 are red and 8 are green.
Dennis takes one apple at random and eats it. Margaret also takes an apple at random and eats it.
By drawing a probability tree diagram, or otherwise, find the probability that Dennis and Margaret eat apples of the same colour. (3 marks)
--- 8 WORK AREA LINES (style=lined) ---
`8/17`
What is the interest earned, in dollars, if $800 is invested for `x` months at a simple interest rate of 3% per annum?
`A`
| `text(Interest)` | `= 800 xx x/12 xx 3/100` |
| `= 2x` |
`=> A`
A person's weight is measured as 79.3 kg.
What is the absolute error of this measurement?
`B`
| `text(A)text(bsolute error)` | `= 1/2 xx\ text(precision)` |
| `= 1/2 xx 0.1\ text(kg)` | |
| `= 1/2 xx 100\ text(grams)` | |
| `= 50\ text(grams)` |
`=> B`
Julia earns $28 per hour. Her hourly pay rate increases by 2%.
How much will she earn for a 4-hour shift with this increase?
`D`
| `text(Hourly rate)` | `= 28 xx 1.02` |
| `= $28.56` |
| `:.\ text(Shift earnings)` | `= 4 xx 28.56` |
| `= $114.24` |
`=> D`