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.
Level 1 · Warm-up
1 I add 7 to a number and get 23. What was the number?
Show worked solution
23 − 7 = 16.
2 I multiply a number by 5 and get 45. What was it?
Show worked solution
45 ÷ 5 = 9.
3 I double a number and add 1, getting 17. What was it?
Show worked solution
17 − 1 = 16, ÷ 2 = 8.
Level 2 · Core
4 I multiply by 3, then subtract 8, and get 19. What was my number?
Show worked solution
19 + 8 = 27, ÷ 3 = 9.
5 Amy had some money, spent $14, earned $6, and now has $22. Start amount?
Show worked solution
22 − 6 + 14 = $30.
6 Half a number, plus 9, equals 25. What is the number?
Show worked solution
25 − 9 = 16, ×2 = 32.
Level 3 · Challenge
7 A jar: half eaten, then half of the rest eaten, then 2 eaten, leaving 7. Start count?
Show worked solution
7 + 2 = 9, ×2 = 18, ×2 = 36.
8 Rule 'triple then subtract 5'. A term is 40. What was the term before?
Show worked solution
40 + 5 = 45, ÷ 3 = 15.
9 I had 600 points, bought 4 shields at 95 each and a helmet, leaving 130. Helmet cost?
Show worked solution
600 − 380 = 220; 220 − 130 = 90.