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: 12, 48, 10, 32? (a) 12 (b) 48 (c) 10 (d) 32
- 2.Which is the odd one out: 24, 32, 96, 58? (a) 24 (b) 32 (c) 96 (d) 58
- 3.Which is the odd one out: 20, 32, 10, 16? (a) 20 (b) 32 (c) 10 (d) 16
- 4.Which is the odd one out: 72, 48, 22, 18? (a) 72 (b) 48 (c) 22 (d) 18
- 5.Which is the odd one out: 38, 12, 32, 24? (a) 38 (b) 12 (c) 32 (d) 24
- 6.Which is the odd one out: 35, 81, 45, 63? (a) 35 (b) 81 (c) 45 (d) 63
- 7.Which is the odd one out: 24, 64, 42, 16? (a) 24 (b) 64 (c) 42 (d) 16
- 8.Which is the odd one out: 16, 62, 48, 24? (a) 16 (b) 62 (c) 48 (d) 24
- 9.Which is the odd one out: 20, 30, 32, 16? (a) 20 (b) 30 (c) 32 (d) 16
- 10.Which is the odd one out: 48, 46, 64, 96? (a) 48 (b) 46 (c) 64 (d) 96
- 11.Which is the odd one out: 16, 64, 32, 30? (a) 16 (b) 64 (c) 32 (d) 30
- 12.Which is the odd one out: 24, 12, 44, 48? (a) 24 (b) 12 (c) 44 (d) 48
- 13.Which is the odd one out: 18, 16, 32, 12? (a) 18 (b) 16 (c) 32 (d) 12
- 14.Which is the odd one out: 81, 45, 63, 35? (a) 81 (b) 45 (c) 63 (d) 35
- 15.Which is the odd one out: 48, 96, 16, 34? (a) 48 (b) 96 (c) 16 (d) 34
- 16.Which is the odd one out: 72, 14, 36, 24? (a) 72 (b) 14 (c) 36 (d) 24
- 17.Which is the odd one out: 27, 49, 63, 81? (a) 27 (b) 49 (c) 63 (d) 81
- 18.Which is the odd one out: 63, 81, 49, 27? (a) 63 (b) 81 (c) 49 (d) 27
- 19.Which is the odd one out: 48, 72, 14, 36? (a) 48 (b) 72 (c) 14 (d) 36
- 20.Which is the odd one out: 32, 30, 16, 24? (a) 32 (b) 30 (c) 16 (d) 24
- 21.Which is the odd one out: 24, 48, 10, 40? (a) 24 (b) 48 (c) 10 (d) 40
- 22.Which is the odd one out: 24, 16, 42, 64? (a) 24 (b) 16 (c) 42 (d) 64
- 23.Which is the odd one out: 20, 38, 40, 16? (a) 20 (b) 38 (c) 40 (d) 16
- 24.Which is the odd one out: 16, 32, 48, 42? (a) 16 (b) 32 (c) 48 (d) 42
- 25.Which is the odd one out: 54, 20, 36, 18? (a) 54 (b) 20 (c) 36 (d) 18
- 26.Which is the odd one out: 16, 32, 84, 64? (a) 16 (b) 32 (c) 84 (d) 64
- 27.Which is the odd one out: 66, 88, 16, 48? (a) 66 (b) 88 (c) 16 (d) 48
- 28.Which is the odd one out: 24, 16, 12, 22? (a) 24 (b) 16 (c) 12 (d) 22
- 29.Which is the odd one out: 72, 54, 46, 24? (a) 72 (b) 54 (c) 46 (d) 24
- 30.Which is the odd one out: 35, 45, 63, 27? (a) 35 (b) 45 (c) 63 (d) 27
- 31.Which is the odd one out: 34, 18, 36, 12? (a) 34 (b) 18 (c) 36 (d) 12
- 32.Which is the odd one out: 48, 36, 22, 72? (a) 48 (b) 36 (c) 22 (d) 72
- 33.Which is the odd one out: 38, 18, 72, 48? (a) 38 (b) 18 (c) 72 (d) 48
- 34.Which is the odd one out: 36, 22, 24, 72? (a) 36 (b) 22 (c) 24 (d) 72
- 35.Which is the odd one out: 60, 48, 24, 20? (a) 60 (b) 48 (c) 24 (d) 20
- 36.Which is the odd one out: 12, 16, 34, 48? (a) 12 (b) 16 (c) 34 (d) 48
- 37.Which is the odd one out: 35, 77, 55, 49? (a) 35 (b) 77 (c) 55 (d) 49
- 38.Which is the odd one out: 86, 24, 16, 96? (a) 86 (b) 24 (c) 16 (d) 96
- 39.Which is the odd one out: 60, 12, 62, 30? (a) 60 (b) 12 (c) 62 (d) 30
- 40.Which is the odd one out: 16, 42, 64, 48? (a) 16 (b) 42 (c) 64 (d) 48
Answer key
- 10
- 58
- 10
- 22
- 38
- 35
- 42
- 62
- 30
- 46
- 30
- 44
- 18
- 35
- 34
- 14
- 49
- 49
- 14
- 30
- 10
- 42
- 38
- 42
- 20
- 84
- 66
- 22
- 46
- 35
- 34
- 22
- 38
- 22
- 20
- 34
- 55
- 86
- 62
- 42
Free maths olympiad lessons, practice and worksheets at talentjr.in/maths-olympiad