Logical Reasoning - Arithmetic Signs

Logical Reasoning skills 

Logical Reasoning - Arithmetic Signs :

Q: 1. Find out the two signs to be interchanged for making following equation correct:

5 + 3 x 8 - 12 / 4 =3

A. + and -

B. - and /

C. + and x

D. + and /

Answer: B. - and /

Explanation:

On interchanging - and /,

we get the equation 

as 5 + 3 x 8 / 12 - 4 = 3

5 + 3 x (2/3) - 4 = 3

3 = 3, which is true.

Q: 2. If 3, 2 = 13;

4, 8 = 80;

then 1, 5 =?

A. 14

B. 26

C. 25

D. 50

Answer: B. 26

Explanation:

The sum of the square of the number

32 + 22 = 9 + 4 = 13

42 + 82 = 16 + 64 = 80

12 + 52 = 1 + 25 = 26.

Q: 3. If 1 = 17

2 = 33

3 = 49

4 = 65

then 5 = ?

A. 80

B. 81

C. 89

D. 84

Answer: B. 81

Explanation:

Multiply by 16 and add 1

(1 x 16) + 1 = 17

(2 x 16) + 1 = 33

(3 x 16) + 1 = 49

(4 x 16) + 1 = 65

(5 x 16) + 1 = 81.

Q: 4. If 2 + 3 = 13

3 + 4 = 25

4 + 5 = 41 then

5 + 6 = ?

A. 60

B. 61

C. 51

D. 63

Answer: B. 61

Explanation:

Step 1 : 

First multiply to the given number

Step 2 : 

Multiply by 2

Step 3 : 

add 1

(2 x 3) x 2 + 1 = 13

(3 x 4) x 2 + 1 = 25

(4 x 5) x 2 + 1 = 41

(5 x 6) x 2 + 1 = 61.

Q: 5. Select the correct set of symbols which will fit in the given equation?

5 0 3 5 = 20

A. x , x, x

B. -, +, x

C. x, + , x

D. +, -, x

Answer: B. -, +, x

Explanation:

Clearly 5 - 0 + 3 x 5 = 5 + 15

= 20

Q: 6. If x stands for 'addition', / stands for 'subtraction', + stands for 'multiplication' and-stands for 'division', then 20 x 8 / 8 - 4 + 2 = ?

A. 80

B. 25

C. 24

D. 5

Answer: C. 24

Explanation:

By the Given data, We have the expression:

20 + 8 - 8 / 4 x 2 = 20 + 8 - 2 x 2

= 20 + 8 - 4

= 24.

7. If 2 + 3 = 10

8 + 4 = 96

7 + 2 = 63

6 + 5 = 66

then 9 + 5 = ?

A. 99

B. 89

C. 116

D. 126

Answer: D. 126

Explanation:

Add the given number and multiply the first number

2 + 3 = 5 x 2 = 10

8 + 4 = 12 x 8 = 96

7 + 2 = 9 x 7 = 63

6 + 5 = 11 x 6 = 66

9 + 5 = 14 x 9 = 126.