Work through the levels in order. Type your answer and press Check — open the worked solution if you get stuck. Answers like -6, 3/4 or 0.25 are typed exactly as shown. A ⭐ Bonus Challenge at the end is extra credit — skip it if the rest was hard work.
15 questions · official format, shuffled order
1 Which list is in order from smallest to largest?
Show worked solution
As thousandths they are 89, 90, 100, 110 and 900, so the order is 0.089, 0.09, 0.1, 0.11, 0.9. More digits does not mean a bigger number.
2 A machine fills 1 000 bottles with 0.375 L each. How many litres is that altogether?
Show worked solution
0.375 × 1 000 = 375 L. Three zeros, three places.
3 A jacket costs $240. It is reduced by 25%, and then the sale price is reduced by a further 10%. What is the final price?
Show worked solution
25% of 240 is 60, so $180. 10% of 180 is 18, so $162. (Taking 35% off $240 in one go gives $156 — the wrong answer.)
4 Which of these is the largest?
Show worked solution
0.42 = 42 hundredths, 2/5 = 40 hundredths, 45% = 45 hundredths, 0.405 = 40.5 hundredths.
5 On this spinner the chance of red is 0.3 and the chance of blue is 0.25. Green and yellow are equally likely. What is the chance of yellow?
Show worked solution
1 − 0.3 − 0.25 = 0.45 for green and yellow together. Half of 0.45 is 0.225.
6 Look at the number 4.075.1 The 7 is worth 7 hundredths.
2 4.075 × 100 = 40.75.
3 4.075 rounded to one decimal place is 4.1.
Which statements are correct?
2 4.075 × 100 = 40.75.
3 4.075 rounded to one decimal place is 4.1.
Which statements are correct?
Show worked solution
The 7 is in the hundredths column (1 ✓). 4.075 × 100 = 407.5, two places not one (2 ✗). The hundredths digit is 7, so 4.0 rounds up to 4.1 (3 ✓). 1 and 3.
7 30% of a number is 24. What is 75% of the same number?
Show worked solution
10% is 8, so the number is 80. 75% of 80 = 3 × 20 = 60.
8 Petrol costs $1.85 a litre. Sam buys 40 litres and pays with $80. How much change does he get?
Show worked solution
$1.85 × 4 = $7.40, so × 40 = $74. $80 − $74 = $6.
9 A 2.5 km straight path has a post every 100 m, including one at each end. How many posts are there?
Show worked solution
2 500 ÷ 100 = 25 gaps, and 25 gaps need 26 posts.
10 45 of the squares in this hundred grid are shaded.1 45% of the grid is shaded.
2 2/5 of the grid is shaded.
3 0.55 of the grid is unshaded.
Which statements are correct?
2 2/5 of the grid is shaded.
3 0.55 of the grid is unshaded.
Which statements are correct?
Show worked solution
45/100 = 45% (1 ✓). 45/100 = 9/20, not 2/5 which is 40/100 (2 ✗). 100 − 45 = 55 unshaded, which is 0.55 (3 ✓). 1 and 3.
11 Which of these numbers is closest to 0.5?
Show worked solution
0.499 is 0.001 away; 0.505 is 0.005 away; 0.52 is 0.020 away; 0.45 is 0.050 away. 0.499.
12 After a 20% discount, a bike costs $420. What was the price before the discount?
Show worked solution
$420 is 80%, so 10% is $52.50 and the original price is $525. (Adding 20% of $420 gives $504, which is wrong: the 20% was of the original, not of the sale price.)
13 0.5 + 0.25 + 0.125 + 0.0625 = ?
Show worked solution
0.5000 + 0.2500 + 0.1250 + 0.0625 = 0.9375.
14 What is 12.5% of 2 kg, in grams?
Show worked solution
12.5% = 1/8. 2 000 ÷ 8 = 250 g.
15 A bag holds 20 marbles. The chance of drawing red is 0.35 and the chance of blue is 0.4. The rest are green. How many green marbles are there?
Show worked solution
1 − 0.35 − 0.4 = 0.25 for green. 0.25 of 20 = 5 marbles.