Each question gives two pairs of numbers set out in the same way, for example: 6 (14) 8 followed by 9 (?) 7. The number inside the brackets is produced from the two numbers either side of it by a hidden rule. Study the first pair to work out the rule, then apply exactly the same rule to the second pair to find the missing number in the brackets. Choose your answer from the five options given. Only one answer is correct for each question.
Worked example. 6 (14) 8
9 (?) 7
Work out the connection between the numbers in the first pair, then use the same connection to find the missing number in the second pair. Answer: 16. The number in brackets is the sum of the two outside numbers: 6 + 8 = 14. Applying the same rule to the second pair: 9 + 7 = 16.
1
8 (17) 9 14 (?) 5
A) 9
B) 70
C) 2.8
D) 20
E) 19
(Total for Question 1 is 1 mark)
2
12 (7) 5 16 (?) 8
A) 24
B) 8
C) 128
D) 2
E) 9
(Total for Question 2 is 1 mark)
3
7 (28) 4 9 (?) 3
A) 12
B) 6
C) 27
D) 3
E) 30
(Total for Question 3 is 1 mark)
4
24 (4) 6 21 (?) 7
A) 28
B) 14
C) 147
D) 3
E) 4
(Total for Question 4 is 1 mark)
5
9 (10) 4 13 (?) 6
A) 14
B) 7
C) 38
D) 4.33
E) 20
(Total for Question 5 is 1 mark)
6
5 (24) 3 6 (?) 4
A) 10
B) 30
C) 20
D) 6
E) 18
(Total for Question 6 is 1 mark)
7
6 (25) 5 8 (?) 3
A) 24
B) 16
C) 21
D) 27
E) 0
(Total for Question 7 is 1 mark)
8
4 (13) 3 7 (?) 5
A) 35
B) 33
C) 47
D) 37
E) 70
(Total for Question 8 is 1 mark)
9
3 (33) 6 4 (?) 7
A) 9
B) 49
C) 53
D) -45
E) 45
(Total for Question 9 is 1 mark)
10
7 (17) 5 9 (?) 6
A) 21
B) 24
C) 15
D) 30
E) 3
(Total for Question 10 is 1 mark)
11
4 (11) 5 7 (?) 8
A) 13
B) 17
C) 24
D) 31
E) 9
(Total for Question 11 is 1 mark)
12
6 (8) 4 9 (?) 5
A) 45
B) 22.5
C) 15
D) 4.67
E) 9
(Total for Question 12 is 1 mark)
13
4 (25) 9 5 (?) 11
A) 126
B) 16
C) 14
D) 36
E) 21
(Total for Question 13 is 1 mark)
14
8 (7) 4 10 (?) 6
A) 8
B) 33
C) 6
D) 8.5
E) 9
(Total for Question 14 is 1 mark)
15
3 (40) 7 5 (?) 9
A) 56
B) 14
C) -56
D) 18
E) 45
(Total for Question 15 is 1 mark)
16
5 (7) 4 7 (?) 3
A) 5
B) 15
C) 18
D) 27
E) -5
(Total for Question 16 is 1 mark)
17
8 (28) 3 11 (?) 5
A) 36
B) 47
C) 41
D) 17
E) 31
(Total for Question 17 is 1 mark)
18
5 (20) 6 7 (?) 8
A) 56
B) 40
C) 49
D) 42
E) 70
(Total for Question 18 is 1 mark)
19
6 (2) 3 12 (?) 4
A) 48
B) 6
C) 1
D) 0.33
E) 3
(Total for Question 19 is 1 mark)
20
5 (14) 3 7 (?) 4
A) 34
B) 17
C) 45
D) 78
E) 56
(Total for Question 20 is 1 mark)
21
9 (56) 4 11 (?) 6
A) 85
B) 74
C) 79
D) -96
E) 96
(Total for Question 21 is 1 mark)
22
7 (40) 3 8 (?) 5
A) -39
B) 9
C) 39
D) 89
E) 6
(Total for Question 22 is 1 mark)
23
6 (18) 4 8 (?) 5
A) 40
B) 34
C) 49
D) 31
E) 37
(Total for Question 23 is 1 mark)
24
4 (35) 8 6 (?) 10
A) 64
B) 7
C) 65
D) 168
E) 63
(Total for Question 24 is 1 mark)
25
8 (43) 3 10 (?) 4
A) 64
B) 60
C) -20
D) 144
E) -26
(Total for Question 25 is 1 mark)
Mark scheme · EP.V18B Number Connections: Practice Set 2
Question 1
B1 E) 19 - rule is addition: 8 + 9 = 17, so 14 + 5 = 19
Answer: 19
Question 2
B1 B) 8 - rule is subtraction: 12 - 5 = 7, so 16 - 8 = 8
Answer: 8
Question 3
B1 C) 27 - rule is multiplication: 7 x 4 = 28, so 9 x 3 = 27
Answer: 27
Question 4
B1 D) 3 - rule is division: 24 / 6 = 4, so 21 / 7 = 3
Answer: 3
Question 5
B1 A) 14 - rule is (subtract, then double): (9 - 4) x 2 = 10, so (13 - 6) x 2 = 14
Answer: 14
Question 6
B1 B) 30 - rule is (add, then multiply by 3): (5 + 3) x 3 = 24, so (6 + 4) x 3 = 30
Answer: 30
Question 7
B1 C) 21 - rule is (multiply, then subtract the second number): (6 x 5) - 5 = 25, so (8 x 3) - 3 = 21
Answer: 21
Question 8
B1 D) 37 - rule is (multiply, then add the difference of the two numbers): (4 x 3) + (4 - 3) = 13, so (7 x 5) + (7 - 5) = 37
Answer: 37
Question 9
B1 E) 45 - rule is (square the second number, subtract the first): 62 - 3 = 33, so 72 - 4 = 45
Answer: 45
Question 10
B1 A) 21 - rule is (double the second number, then add the first): (5 x 2) + 7 = 17, so (6 x 2) + 9 = 21
Answer: 21
Question 11
B1 B) 17 - rule is (multiply the second number by 3, subtract the first): (3 x 5) - 4 = 11, so (3 x 8) - 7 = 17
Answer: 17
Question 12
B1 C) 15 - rule is (multiply, then divide by 3): (6 x 4) / 3 = 8, so (9 x 5) / 3 = 15
Answer: 15
Question 13
B1 D) 36 - rule is (square the first number, add the second): 42 + 9 = 25, so 52 + 11 = 36
Answer: 36
Question 14
B1 E) 9 - rule is (find the mean, then add one): ((8 + 4) / 2) + 1 = 7, so ((10 + 6) / 2) + 1 = 9
Answer: 9
Question 15
B1 A) 56 - rule is (add the numbers, multiply by their difference in reverse order): (3 + 7) x (7 - 3) = 40, so (5 + 9) x (9 - 5) = 56
Answer: 56
Question 16
B1 B) 15 - rule is (treble the first number, subtract double the second): (3 x 5) - (2 x 4) = 7, so (3 x 7) - (2 x 3) = 15
Answer: 15
Question 17
B1 C) 41 - rule is (square the difference, then add the second number): (8 - 3)2 + 3 = 28, so (11 - 5)2 + 5 = 41
Answer: 41
Question 18
B1 D) 42 - rule is (multiply, then subtract twice the first number): (5 x 6) - (2 x 5) = 20, so (7 x 8) - (2 x 7) = 42
Answer: 42
Question 19
B1 E) 3 - rule is (multiply, then divide by the sum of the two numbers): (6 x 3) / (6 + 3) = 2, so (12 x 4) / (12 + 4) = 3
Answer: 3
Question 20
B1 A) 34 - rule is (multiply, subtract the sum, then double the result): ((5 x 3) - (5 + 3)) x 2 = 14, so ((7 x 4) - (7 + 4)) x 2 = 34
Answer: 34
Question 21
B1 B) 74 - rule is (add the numbers, multiply by their difference, then subtract the first number): (9 + 4) x (9 - 4) - 9 = 56, so (11 + 6) x (11 - 6) - 11 = 74
Answer: 74
Question 22
B1 C) 39 - rule is (square each number, then subtract the second square from the first): 72 - 32 = 40, so 82 - 52 = 39
Answer: 39
Question 23
B1 D) 31 - rule is (multiply, then subtract three times the difference of the numbers): (6 x 4) - ((6 - 4) x 3) = 18, so (8 x 5) - ((8 - 5) x 3) = 31
Answer: 31
Question 24
B1 E) 63 - rule is (find the mean, square it, then subtract one): ((4 + 8) / 2)2 - 1 = 35, so ((6 + 10) / 2)2 - 1 = 63
Answer: 63
Question 25
B1 A) 64 - rule is (square the first number, subtract the product of the two numbers, then add the second number back): 82 - (8 x 3) + 3 = 43, so 102 - (10 x 4) + 4 = 64