Year 8 Maths

Algebra

100

Evaluate the expression 2x − 3y when x = -2 and y = 9 

-27 

200

A plumber charges a $70 call-out fee and then $90 per hour. Write an expression for the total cost (C) of calling a plumber out for (x) hours.

C=70+90x

300

Write an expression for the following statement and then expand it to solve

A number w is tripled, and then 5 is subtracted. The result is doubled.

6w - 10

400

A box has a height of x cm. It is 3 times as wide as it is high, and 2 times as long as it is wide. Find an expression for the volume of the box, given that volume = length × breadth × height.

18x³

500

Factorise and simplify the following expression: 

7p+14pq

7p(1+2q)

Perimeter, Area and Volume

100

Jennifer needs to fence her country house block to keep her dog in. The block is a rectangle with length 50 m and breadth 42 m. Fencing costs $13 per metre. What will be the total cost of fencing?

$2,392

200

Find the area of a square if it's perimeter is 20cm.

25cm²

300

Calculate the perimeter of a circle with a diameter of 6cm. Answer correct to 1 decimal place. 

18.8cm

400

What is the height of a triangle that has a base of 13 cm and an area of 45.5 cm².

7cm

500

Water is being poured into a fish tank at a rate of 2 L every 10 seconds. The tank is 1.2 m long by 1 m wide by 0.8 m high. How long will it take to fi ll the tank? Give the answer in minutes.

8 minutes 

Percentages

100

Express 60c as a percentage of $5 

12%

200

Decrease $63 by 15%

$53.55

300

Calculate the pre-GST price if the final cost to the consumer was $352

$320

400

Gemma purchased a $400 foal, which she later sold for $750. Calculate the percentage profit Gemma made.

87.5%

500

Three different brands of washing powder are on sale. Their prices are shown below.

Work out which brand provides the best value for money.

A) 400g for $2.56

B) 750 g for $5.10

C) 1.2 kg for $7.38

C) 1.2kg for $7.38

Random

100

What is the y intercept of the linear equation 

y= 3x - 1 

-1

200

The point A (-2, 3) is reflected in the y axis. What is point A's new coordinates? 

(2,3)

300

Angle T is complementary to angle Q and co-interior to angle R.

If Q = 60°, what is the size of R?

T= 30^o so, R= 150^o

400

The two base angles of an isosceles triangle are equal to 2x and 50 respectively. 

What is the value of x?

x = 25

500

Sarah has achieved 72%, 76% and 84% in her last three assessment tasks. After she received her fourth assessment task result, her new average is 80%

What percentage did Marlene achieve on her fourth assessment task?                    

88%