Odd One Out Worksheet for Maths Olympiad
How to solve it (Find the shared rule): Check whether all the numbers are odd or all even — if so, look deeper. Try the tables 3, 4, 5, 6, 7, 8 and 9: which one has three of the numbers in it? The number that is not in that table is the odd one out.
NameDateTime takenScore ___ / 40
- 1.Which is the odd one out: 96, 48, 32, 76? (a) 96 (b) 48 (c) 32 (d) 76
- 2.Which is the odd one out: 96, 42, 48, 24? (a) 96 (b) 42 (c) 48 (d) 24
- 3.Which is the odd one out: 20, 14, 40, 32? (a) 20 (b) 14 (c) 40 (d) 32
- 4.Which is the odd one out: 66, 32, 16, 48? (a) 66 (b) 32 (c) 16 (d) 48
- 5.Which is the odd one out: 42, 54, 56, 18? (a) 42 (b) 54 (c) 56 (d) 18
- 6.Which is the odd one out: 27, 33, 81, 99? (a) 27 (b) 33 (c) 81 (d) 99
- 7.Which is the odd one out: 45, 35, 81, 27? (a) 45 (b) 35 (c) 81 (d) 27
- 8.Which is the odd one out: 20, 32, 14, 40? (a) 20 (b) 32 (c) 14 (d) 40
- 9.Which is the odd one out: 96, 80, 16, 30? (a) 96 (b) 80 (c) 16 (d) 30
- 10.Which is the odd one out: 27, 63, 81, 35? (a) 27 (b) 63 (c) 81 (d) 35
- 11.Which is the odd one out: 80, 16, 30, 48? (a) 80 (b) 16 (c) 30 (d) 48
- 12.Which is the odd one out: 24, 72, 18, 62? (a) 24 (b) 72 (c) 18 (d) 62
- 13.Which is the odd one out: 35, 49, 77, 55? (a) 35 (b) 49 (c) 77 (d) 55
- 14.Which is the odd one out: 32, 24, 16, 18? (a) 32 (b) 24 (c) 16 (d) 18
- 15.Which is the odd one out: 96, 36, 48, 24? (a) 96 (b) 36 (c) 48 (d) 24
- 16.Which is the odd one out: 16, 30, 80, 32? (a) 16 (b) 30 (c) 80 (d) 32
- 17.Which is the odd one out: 27, 65, 45, 81? (a) 27 (b) 65 (c) 45 (d) 81
- 18.Which is the odd one out: 80, 46, 40, 32? (a) 80 (b) 46 (c) 40 (d) 32
- 19.Which is the odd one out: 64, 32, 30, 80? (a) 64 (b) 32 (c) 30 (d) 80
- 20.Which is the odd one out: 70, 16, 40, 56? (a) 70 (b) 16 (c) 40 (d) 56
- 21.Which is the odd one out: 10, 40, 12, 48? (a) 10 (b) 40 (c) 12 (d) 48
- 22.Which is the odd one out: 40, 16, 80, 74? (a) 40 (b) 16 (c) 80 (d) 74
- 23.Which is the odd one out: 72, 18, 54, 40? (a) 72 (b) 18 (c) 54 (d) 40
- 24.Which is the odd one out: 24, 16, 40, 30? (a) 24 (b) 16 (c) 40 (d) 30
- 25.Which is the odd one out: 36, 40, 30, 18? (a) 36 (b) 40 (c) 30 (d) 18
- 26.Which is the odd one out: 30, 16, 48, 32? (a) 30 (b) 16 (c) 48 (d) 32
- 27.Which is the odd one out: 12, 14, 36, 54? (a) 12 (b) 14 (c) 36 (d) 54
- 28.Which is the odd one out: 24, 48, 64, 76? (a) 24 (b) 48 (c) 64 (d) 76
- 29.Which is the odd one out: 18, 12, 32, 16? (a) 18 (b) 12 (c) 32 (d) 16
- 30.Which is the odd one out: 54, 24, 48, 96? (a) 54 (b) 24 (c) 48 (d) 96
- 31.Which is the odd one out: 30, 24, 32, 40? (a) 30 (b) 24 (c) 32 (d) 40
- 32.Which is the odd one out: 16, 24, 28, 42? (a) 16 (b) 24 (c) 28 (d) 42
- 33.Which is the odd one out: 12, 30, 40, 32? (a) 12 (b) 30 (c) 40 (d) 32
- 34.Which is the odd one out: 18, 32, 54, 12? (a) 18 (b) 32 (c) 54 (d) 12
- 35.Which is the odd one out: 32, 16, 80, 60? (a) 32 (b) 16 (c) 80 (d) 60
- 36.Which is the odd one out: 38, 48, 16, 12? (a) 38 (b) 48 (c) 16 (d) 12
- 37.Which is the odd one out: 96, 16, 24, 26? (a) 96 (b) 16 (c) 24 (d) 26
- 38.Which is the odd one out: 16, 30, 32, 80? (a) 16 (b) 30 (c) 32 (d) 80
- 39.Which is the odd one out: 40, 20, 24, 18? (a) 40 (b) 20 (c) 24 (d) 18
- 40.Which is the odd one out: 16, 40, 20, 64? (a) 16 (b) 40 (c) 20 (d) 64
Answer key
- 76
- 42
- 14
- 66
- 56
- 33
- 35
- 14
- 30
- 35
- 30
- 62
- 55
- 18
- 36
- 30
- 65
- 46
- 30
- 70
- 10
- 74
- 40
- 30
- 40
- 30
- 14
- 76
- 18
- 54
- 30
- 42
- 30
- 32
- 60
- 38
- 26
- 30
- 18
- 20
Free maths olympiad lessons, practice and worksheets at talentjr.in/maths-olympiad