Q1.
If '+' means '×', '−' means '÷', '×' means '−', and '÷' means '+', then what is the value of 8 − 4 × 2 + 6 ÷ 3?
- 12
- 10
- 8
- 6
Show answer
Answer: B. 10
Replace each symbol with its respective operation: 8 ÷ 4 − 2 × 6 + 3. This becomes 2 − 12 + 3 = 10.
Q2.
If 'A' means '+', 'B' means '−', 'C' means '×', and 'D' means '÷', then what is the value of 24 D 6 A 15 B 5 C 2?
- 9
- 12
- 15
- 18
Show answer
Answer: A. 9
Given symbols and their meanings:
'A' = '+'
'B' = '−'
'C' = '×'
'D' = '÷'
The expression is: 24 D 6 A 15 B 5 C 2
Substituting the symbols:
24 ÷ 6 + 15 − 5 × 2
Following the BODMAS/PEMDAS rule:
1. Division: 24 ÷ 6 = 4
Expression becomes: 4 + 15 − 5 × 2
2. Multiplication: 5 × 2 = 10
Expression becomes: 4 + 15 − 10
3. Addition: 4 + 15 = 19
Expression becomes: 19 − 10
4. Subtraction: 19 − 10 = 9
Thus, the value of the expression is 9.
Q3.
Which of the following interchanges of signs would make the given equation correct?
18 + 6 ÷ 3 - 2 × 4 = 18
- + and ÷
- - and ×
- + and -
- ÷ and ×
Show answer
Answer: B. - and ×
Given equation: 18 + 6 ÷ 3 - 2 × 4 = 18
Let's first calculate the current value of the left side:
18 + (6 ÷ 3) - (2 × 4)
= 18 + 2 - 8
= 20 - 8
= 12
The current value (12) is not equal to the target value (18). We need to interchange signs to make it correct.
Let's check the options:
1. Interchange '+' and '÷':
18 ÷ 6 + 3 - 2 × 4
= 3 + 3 - 8
= 6 - 8 = -2. (Incorrect)
2. Interchange '-' and '×':
18 + 6 ÷ 3 × 2 - 4
= 18 + 2 × 2 - 4
= 18 + 4 - 4
= 22 - 4 = 18. (Correct)
3. Interchange '+' and '-':
18 - 6 ÷ 3 + 2 × 4
= 18 - 2 + 8
= 16 + 8 = 24. (Incorrect)
4. Interchange '÷' and '×':
18 + 6 × 3 - 2 ÷ 4
= 18 + 18 - 0.5
= 36 - 0.5 = 35.5. (Incorrect)
Therefore, interchanging '-' and '×' makes the equation correct.
Q4.
If 5 * 3 = 34 and 6 * 2 = 40, then 7 * 1 = ?
- 48
- 50
- 52
- 54
Show answer
Answer: B. 50
Let's analyze the given examples to find the pattern:
1. 5 * 3 = 34
Here, 5² + 3² = 25 + 9 = 34. The pattern seems to be A * B = A² + B².
2. 6 * 2 = 40
Using the same pattern: 6² + 2² = 36 + 4 = 40. This confirms the pattern.
Now, apply the pattern to find 7 * 1:
7 * 1 = 7² + 1²
= 49 + 1
= 50
Thus, 7 * 1 = 50.
Q5.
If 'P' denotes '÷', 'Q' denotes '×', 'R' denotes '+', and 'S' denotes '−', then what is the value of 48 P 12 R 15 S 6 Q 3?
- 1
- 5
- 10
- 12
Show answer
Answer: A. 1
Given symbols and their meanings:
'P' = '÷'
'Q' = '×'
'R' = '+'
'S' = '−'
The expression is: 48 P 12 R 15 S 6 Q 3
Substituting the symbols:
48 ÷ 12 + 15 − 6 × 3
Following the BODMAS/PEMDAS rule:
1. Division: 48 ÷ 12 = 4
Expression becomes: 4 + 15 − 6 × 3
2. Multiplication: 6 × 3 = 18
Expression becomes: 4 + 15 − 18
3. Addition: 4 + 15 = 19
Expression becomes: 19 − 18
4. Subtraction: 19 − 18 = 1
Thus, the value of the expression is 1.
Q6.
Which two numbers need to be interchanged to make the following equation correct?
18 ÷ 3 + 5 × 2 - 7 = 15
- 3 and 5
- 2 and 7
- 18 and 7
- 5 and 7
Show answer
Answer: D. 5 and 7
Given equation: 18 ÷ 3 + 5 × 2 - 7 = 15
Let's first calculate the current value of the left side:
(18 ÷ 3) + (5 × 2) - 7
= 6 + 10 - 7
= 16 - 7
= 9
The current value (9) is not equal to the target value (15). We need to interchange two numbers.
Let's check the options:
1. Interchange 3 and 5:
18 ÷ 5 + 3 × 2 - 7
= 3.6 + 6 - 7
= 9.6 - 7 = 2.6. (Incorrect)
2. Interchange 2 and 7:
18 ÷ 3 + 5 × 7 - 2
= 6 + 35 - 2
= 41 - 2 = 39. (Incorrect)
3. Interchange 18 and 7:
7 ÷ 3 + 5 × 2 - 18
= 2.33 (approx) + 10 - 18
= 12.33 - 18 = -5.67 (approx). (Incorrect)
4. Interchange 5 and 7:
18 ÷ 3 + 7 × 2 - 5
= 6 + 14 - 5
= 20 - 5 = 15. (Correct)
Therefore, interchanging 5 and 7 makes the equation correct.
Q7.
Select the correct combination of mathematical signs to replace '*' signs and balance the given equation.
25 * 5 * 3 * 10 * 2 = 15
- ÷, +, -, ×
- +, -, ×, ÷
- ×, ÷, +, -
- -, ×, ÷, +
Show answer
Answer: B. +, -, ×, ÷
Given equation: 25 * 5 * 3 * 10 * 2 = 15
We need to replace the '*' signs with the operators from the options to make the equation true.
Let's check each option:
1. ÷, +, -, ×:
25 ÷ 5 + 3 - 10 × 2
= 5 + 3 - 20
= 8 - 20 = -12. (Incorrect)
2. +, -, ×, ÷:
25 + 5 - 3 × 10 ÷ 2
= 25 + 5 - (3 × 10) ÷ 2
= 25 + 5 - 30 ÷ 2
= 25 + 5 - 15
= 30 - 15 = 15. (Correct)
3. ×, ÷, +, -:
25 × 5 ÷ 3 + 10 - 2
= 125 ÷ 3 + 10 - 2
= 41.66 (approx) + 10 - 2 = 49.66 (approx). (Incorrect)
4. -, ×, ÷, +:
25 - 5 × 3 ÷ 10 + 2
= 25 - (5 × 3) ÷ 10 + 2
= 25 - 15 ÷ 10 + 2
= 25 - 1.5 + 2
= 23.5 + 2 = 25.5. (Incorrect)
Therefore, the combination '+, -, ×, ÷' makes the equation correct.
Q8.
If 12 $ 3 = 36, 15 $ 5 = 75, then 20 $ 4 = ?
- 60
- 70
- 80
- 90
Show answer
Answer: C. 80
Let's analyze the given examples to find the pattern:
1. 12 $ 3 = 36
Here, 12 × 3 = 36. The pattern seems to be A $ B = A × B.
2. 15 $ 5 = 75
Using the same pattern: 15 × 5 = 75. This confirms the pattern.
Now, apply the pattern to find 20 $ 4:
20 $ 4 = 20 × 4
= 80
Thus, 20 $ 4 = 80.
Q9.
If '+' means '×', '−' means '÷', '×' means '−', and '÷' means '+', then what is the value of 16 ÷ 8 − 4 + 2 × 5?
- 15
- 18
- 20
- 22
Show answer
Answer: A. 15
Given symbols and their meanings:
'+' means '×'
'−' means '÷'
'×' means '−'
'÷' means '+'
The expression is: 16 ÷ 8 − 4 + 2 × 5
Substituting the symbols:
16 + 8 ÷ 4 × 2 − 5
Following the BODMAS/PEMDAS rule:
1. Division: 8 ÷ 4 = 2
Expression becomes: 16 + 2 × 2 − 5
2. Multiplication: 2 × 2 = 4
Expression becomes: 16 + 4 − 5
3. Addition: 16 + 4 = 20
Expression becomes: 20 − 5
4. Subtraction: 20 − 5 = 15
Thus, the value of the expression is 15.
Q10.
Select the correct combination of mathematical signs to replace '*' signs and balance the given equation.
36 * 6 * 2 * 18 * 3 = 27
- ÷, +, -, ×
- ×, ÷, +, -
- ÷, ×, +, -
- +, -, ×, ÷
Show answer
Answer: C. ÷, ×, +, -
Given equation: 36 * 6 * 2 * 18 * 3 = 27
We need to replace the '*' signs with the operators from the options to make the equation true.
Let's check each option:
1. ÷, +, -, ×:
36 ÷ 6 + 2 - 18 × 3
= 6 + 2 - 54
= 8 - 54 = -46. (Incorrect)
2. ×, ÷, +, -:
36 × 6 ÷ 2 + 18 - 3
= 216 ÷ 2 + 18 - 3
= 108 + 18 - 3
= 126 - 3 = 123. (Incorrect)
3. ÷, ×, +, -:
36 ÷ 6 × 2 + 18 - 3
= 6 × 2 + 18 - 3
= 12 + 18 - 3
= 30 - 3 = 27. (Correct)
4. +, -, ×, ÷:
36 + 6 - 2 × 18 ÷ 3
= 36 + 6 - 36 ÷ 3
= 36 + 6 - 12
= 42 - 12 = 30. (Incorrect)
Therefore, the combination '÷, ×, +, -' makes the equation correct.
Q11.
If A @ B = A + B when A > B, and A @ B = A × B when A ≤ B, then what is the value of (10 @ 5) @ (3 @ 7)?
- 36
- 315
- 34
- 26
Show answer
Answer: B. 315
Given rule for the operator '@':
If A > B, then A @ B = A + B
If A ≤ B, then A @ B = A × B
We need to find the value of (10 @ 5) @ (3 @ 7).
Step 1: Evaluate (10 @ 5)
Here, A = 10 and B = 5. Since A (10) > B (5), we use the rule A @ B = A + B.
10 @ 5 = 10 + 5 = 15.
Step 2: Evaluate (3 @ 7)
Here, A = 3 and B = 7. Since A (3) ≤ B (7), we use the rule A @ B = A × B.
3 @ 7 = 3 × 7 = 21.
Step 3: Evaluate the final expression (15 @ 21)
Now we have 15 @ 21. Here, A = 15 and B = 21. Since A (15) ≤ B (21), we use the rule A @ B = A × B.
15 @ 21 = 15 × 21
To calculate 15 × 21:
15 × 20 = 300
15 × 1 = 15
300 + 15 = 315
Thus, the value of (10 @ 5) @ (3 @ 7) is 315.
Q12.
Select the correct combination of mathematical signs to replace '*' signs and balance the given equation.
24 * 4 * 5 * 2 = 14
- ÷, +, -
- +, -, ×
- ×, ÷, -
- -, ×, ÷
Show answer
Answer: D. -, ×, ÷
Given equation: 24 * 4 * 5 * 2 = 14
We need to replace the '*' signs with the operators from the options to make the equation true.
Let's check each option:
1. ÷, +, -:
24 ÷ 4 + 5 - 2
= 6 + 5 - 2
= 11 - 2 = 9. (Incorrect)
2. +, -, ×:
24 + 4 - 5 × 2
= 28 - 10
= 18. (Incorrect)
3. ×, ÷, -:
24 × 4 ÷ 5 - 2
= 96 ÷ 5 - 2
= 19.2 - 2 = 17.2. (Incorrect)
4. -, ×, ÷:
24 - 4 × 5 ÷ 2
= 24 - (4 × 5) ÷ 2
= 24 - 20 ÷ 2
= 24 - 10 = 14. (Correct)
Therefore, the combination '-, ×, ÷' makes the equation correct.
Q13.
If 'L' means '+', 'M' means '−', 'N' means '×', 'P' means '÷', then what is the value of 28 P 7 N 12 L 15 M 10?
- 53
- 48
- 58
- 63
Show answer
Answer: A. 53
Given symbols and their meanings:
'L' = '+'
'M' = '−'
'N' = '×'
'P' = '÷'
The expression is: 28 P 7 N 12 L 15 M 10
Substituting the symbols:
28 ÷ 7 × 12 + 15 − 10
Following the BODMAS/PEMDAS rule:
1. Division: 28 ÷ 7 = 4
Expression becomes: 4 × 12 + 15 − 10
2. Multiplication: 4 × 12 = 48
Expression becomes: 48 + 15 − 10
3. Addition: 48 + 15 = 63
Expression becomes: 63 − 10
4. Subtraction: 63 − 10 = 53
Thus, the value of the expression is 53.
Q14.
If 4 # 2 = 26, 6 # 3 = 39, then 8 # 4 = ?
- 48
- 52
- 56
- 60
Show answer
Answer: B. 52
Let's analyze the given examples to find the pattern for the operator '#':
1. 4 # 2 = 26
If we try (A × 5) + (B × 3):
(4 × 5) + (2 × 3) = 20 + 6 = 26. This matches.
2. 6 # 3 = 39
Using the same pattern:
(6 × 5) + (3 × 3) = 30 + 9 = 39. This also matches.
The pattern is confirmed: A # B = (A × 5) + (B × 3).
Now, apply the pattern to find 8 # 4:
8 # 4 = (8 × 5) + (4 × 3)
= 40 + 12
= 52
Thus, 8 # 4 = 52.
Q15.
If 'a' means 'add', 'b' means 'subtract', 'c' means 'multiply', 'd' means 'divide', and 'e' means 'exponentiate (power of)', then what is the value of 10 c (5 a 3) d 4 b (2 e 3)?
- 12
- 16
- 20
- 24
Show answer
Answer: A. 12
Given symbols and their meanings:
'a' = 'add' (+)
'b' = 'subtract' (-)
'c' = 'multiply' (×)
'd' = 'divide' (÷)
'e' = 'exponentiate' (power of)
The expression is: 10 c (5 a 3) d 4 b (2 e 3)
Following the order of operations (BODMAS/PEMDAS), we first solve the expressions within parentheses:
1. (5 a 3): Substitute 'a' with '+'
5 + 3 = 8
2. (2 e 3): Substitute 'e' with 'exponentiate'
2³ = 2 × 2 × 2 = 8
Now substitute these values back into the main expression:
10 c 8 d 4 b 8
Next, substitute the remaining symbols with their mathematical operators:
10 × 8 ÷ 4 - 8
Now, follow BODMAS/PEMDAS for the remaining operations:
1. Multiplication: 10 × 8 = 80
Expression becomes: 80 ÷ 4 - 8
2. Division: 80 ÷ 4 = 20
Expression becomes: 20 - 8
3. Subtraction: 20 - 8 = 12
Thus, the value of the expression is 12.