Calculations and BIMDAS
Round 8.647 to 1 decimal place.
8.6
Write 0.35 as a percentage.
35%
Convert 2.4 km into metres.
2 400 m
Which type of graph is best for showing how rainfall changes across 12 months?
A line graph
Simplify the ratio 20 : 30.
2 : 3
Evaluate: 7 + 4 × 3
19 (multiply first: 7 + 12)
Find 20% of $450.
$90 (0.2 × 450)
Find the area of a rectangular shed floor 9 m by 6.5 m.
58.5 m²
Name the three things every graph you draw must have.
A title, both axes labelled (with units), and an even scale
A quad bike is priced at $6 500 before GST. How much GST (10%) is added?
$650
Estimate 59 × 21 by rounding both numbers to the nearest 10.
60 × 20 = 1 200 (actual 1 239)
Express 27 out of 60 as a percentage.
45% (27 ÷ 60 × 100)
A paddock measures 600 m by 500 m. How many hectares is it?
30 ha (300 000 m² ÷ 10 000)
On a step graph, what does an open circle (○) at the end of a step mean?
That value is NOT included in that step — it belongs to the next one
Convert 90 km/h into metres per second.
25 m/s (90 ÷ 3.6)
Evaluate: (9 + 3)² ÷ 4
36 (brackets → 12² = 144, then 144 ÷ 4)
A ute travels 480 km in 6 hours. What is its average speed?
80 km/h (480 ÷ 6)
A rectangular tank is 4 m long, 2.5 m wide and 2 m high.
Find its volume, then state how many litres it holds.
20 m³ = 20 000 L
A column graph has a vertical axis that starts at 80 instead of 0.
Why is this misleading?
It exaggerates the difference between the columns — a small gap looks huge
Calculate the simple interest on $8 000 invested at 5% per annum for 4 years.
$1 600 (I = 8 000 × 0.05 × 4)
The cost of hiring a tractor is C = 120h + 250, where h is the number of hours.
Find the cost of hiring it for 7.5 hours.
$1 150 (120 × 7.5 = 900, then 900 + 250)
A worker is paid $26.40 per hour. Last week she worked 38 normal hours plus 4 hours at double time.
What were her total earnings?
$1 214.40 (38 × 26.40 = $1 003.20; 4 × $52.80 = $211.20)
A concrete pad is 12 m long, 8 m wide and 150 mm thick.
How many cubic metres of concrete are needed?
14.4 m³ (150 mm = 0.15 m; 12 × 8 × 0.15)
In a two-way table, 40 Year 11 and 35 Year 12 students play a sport, while 20 Year 11 and 25 Year 12 do not.
What percentage of all the students play a sport?
62.5% (75 out of 120)
A feed mix uses oats, lupins and barley in the ratio 4 : 3 : 1.
How much of each is needed to make 1 200 kg?
600 kg oats, 450 kg lupins, 150 kg barley (8 shares of 150 kg)