Free Practice Questions for Mathematical-operation in Reasoning

By examining all the alternatives we can check for the correct symbols that make the equation true:

$10+5-4 \times 3 \div 6=13$

Solving from the left,

$15-2=13$

$13 = 13$

After the signs of option (1), (×, –, ÷, +, = ) is placed in the given equation we get:
17 × 3 - 6 ÷ 2 + 7 = 55
On solving the L.H.S we get:
→ 51 – 3 + 7
→ 51 + 4 → 55
So, L.H.S = R.H.S
As,
By checking the 1st option we have got the correct answer therefore now we don’t need to check other options.
Hence, option (1) is the correct answer.

8 × 4 – 7 + 8 ÷ 2 = 35
After changing the two signs of option (1), (+ and –) the equation becomes:
8 × 4 + 7 – 8 ÷ 2 = 35
On solving L.H.S;
→ 32 + 7 – 4
→ 39 – 4 → 35
Thus L.H.S = R.H.S
As,
By checking the 1st option we have got the correct answer therefore now we don’t need to check other options.
Hence, option (1) is the correct answer.

This type of questions are solved by hit and trail method,

(38 A 17) B 9 C 117 D 13 E 94 = 104

Replace letter by –, ×, +, ÷, –

(38 A 17) B 9 C 117 D 13 E 94 = 104

(38-17) ×9+117÷13-94=104

Apply BODMAS

189+9-94=104

104=104

Hence, option (1) is the correct answer.

This type of questions are solved by hit and trail method so replace 8 and 3

186 ÷ 17 + 104 – 12 × 3 = 16

136 ÷ 17 + 104 – 12 × 8 = 16

Apply BODMAS

8+104-96=16

112-96=16

16=16

Hence, option (2) is the correct answer.

To balance the given equation we will have to check options, that is given below;

By checking option (1):

46 × 6 + 32 - 12 ÷ 8 = - 34

After interchanging the signs & numbers of option (1), (8 and 6; ÷ and ×)

48 × 6 + 32 – 12 ÷ 6 = - 34

or, 48 ÷ 8 +32 -12 × 6 = - 34

or, 6 +32 – 72 = -34

or, 38 – 72 = - 34

or, -34 = -34

so, its correct option.

as, we found the correct answer, so no need to check more options.

Hence, option (1) is the correct answer.

Mathematical operations

÷ is interchanged with +,

 × is interchanged with -,

By checking option (1):

24 × 84 + 12 ÷ 16 - 7 = 129

After interchanging the signs;

24 - 84 ÷ 12 + 16 × 7 = 129

or, 24 - 7 + 112 = 129

or, 129=129

so, its correct option.

as, we found the correct answer, so no need to check more options.

Hence, option (1) is the correct answer.

As per the given information in the question;

14 B (18 D 3) A 5 B 7 C 12 B (24 D 4)

A →+,

B → ×

C → -

D → ÷

After the letters are replaced with signs the equation becomes:

→ 14 × (18 ÷ 3) + 5 × 7 - 12 × (24 ÷ 4)

→ 14 × 6 + 5 × 7 - 12 × 6

→ 84 + 5 × 7 – 72

→ 119 – 72

= 47

Hence, option (1) is the correct answer.

After checking all the options we find that the numbers in option (4) when interchanged will make the equation correct:

14 + 32 – 56 ÷ 28 × 5 = 40

After interchanging the numbers of option (4), (28 and 14)

28 + 32 – 56 ÷ 14 × 5 = 40

On solving L.H.S;

→ 28 + 32 – 56 ÷ 14 × 5

→ 28 + 32 – 4 × 5

→ 28 + 32 – 20

→ 60 - 20 = 40

Thus, L.H.S = R.H.S

Hence, option (4) is the correct answer.

when we change the signs according the question in option (2) then,

÷ is changed to +

× is changed to +

+ is changed to ×

− is changed to ÷

26  × 18  ÷ 36 + 4 + 102 = 119

 Therefore, option (2) is the correct answer.

$\mathrm{A} \rightarrow-$
$\mathrm{B} \rightarrow+$
$\mathrm{C} \rightarrow \dot{\mathrm{x}}$
$\mathrm{D} \rightarrow \div$
$96 \div 12-6+3 \dot{\mathrm{x}} 5=8-6+15=23-6=17$

This can be solve by hit and trial method, so put the mathematical signs shown in option 3 into the given equation and replace * sign
11 * 4 * 3 * 3 * 7 * 8
Apply BODMAS
11+4×3÷3-7=8
11+4×1-7=8
11+4-7=8
15-7=8
8=8
Hence, option (3) is the correct answer.

as per given equation;

17 × 3 ÷ 6 − 2 + 7 = 55

This type of question is solved by hit and trial method, 

so after replace the signs of option (2), (÷ and –)

17 × 3 - 6 ÷ 2 + 7 = 55

51 - 3 + 7 = 55

58 - 3 = 55

55 = 55

Hence, option (2) is the correct answer.

As per given equation;

36 – 6÷ 6 × 6 + 30 = 0

After interchanging the two signs given in option (1),(– and $\div$) we get the equation as:

36 ÷ 6 – 6 × 6 + 30 = 0

On solving the L.H.S we get;

→ 6 – 36 + 30

→ 6 + 30 – 36

→  36 – 36 = 0

→ L.H.S = R.H.S

As we get the correct answer there is no need to further check for the other options.

Hence, option (1) is the correct answer.

as per given equation;

72 * 4 * 15 * 3 * 12 = 51

After putting the given signs in option (1), (÷, +, ×, –) in the equation we get;

72 ÷ 4 + 15 × 3 - 12 = 51

On solving L.H.S we get;

→ 72 ÷ 4 + 15 × 3 – 12

→ 18 + 15 × 3 – 12

→ 51,

→ L.H.S = R.H.S

As we get the answer thus there is no need to check for further options.

Hence, option (1) is the correct answer.

The given expression is

52 ÷ 4 – 7 × 5 + 3

After interchangethe digits (7 and 2) and (3 and 4)

57 ÷ 3 – 2 × 5 + 4

Apply BODMAS

19-10+4

9+4=13

Hence, option (4) is the correct answer.

Given expression is

18 ÷ 6 × 3 – 4 + 5

+→ ×

×→÷

÷→ –

– → +

Change signs as per the question;

18 - 6 ÷ 3 + 4 × 5

Apply BODMAS

18-2+20

=36

Hence, option (1) is the correct answer.

When the two signs interchange as given in the options the equation becomes:

128 + 8 × 2 ÷ 4 – 6 = 30

1). After interchange with given signs of option (1),(× and –):

128 + 8 – 2 ÷ 4 × 6 = 30

On solving L.H.S we get;

128 + 8 – 2 ÷ 4 × 6

→ 128 + 8 – 3

→ 133

So, L.H.S is not equal to R.H.S

2).After interchange with given signs of option (2), (÷ and –):

128 + 8 × 2 ÷ 4 – 6 = 30

128 + 8 × 2 – 4 ÷ 6 = 30

On solving L.H.S we get;

→ 128 + 16 – 4 ÷ 6

→ 143.33

So, L.H.S is not equal to R.H.S

3). After interchange with given signs of option (3), (÷ and +):

128 + 8 × 2 ÷ 4 – 6 = 30

128 ÷ 8 × 2 + 4 – 6 = 30

On solving L.H.S we get;

→ 16 × 2 + 4 – 6

→ 32 + 4 – 6

→ 30

So, L.H.S = R.H.S

As we get the correct answer we don’t need to check further.

Hence, option (3) is the correct answer.

By checking all the options:

8 * 20 * 320 * 20 * 10 = 166

Put the signs of option (1), (+, ×, –, ÷)  to check the equation;

(1) 8 + 20 × 320 - 20 ÷ 10 = 166

On solving L.H.S we get;

→ 6406 ≠ 166 (incorrect)

(2) Put the signs of option (1), (×, +, ÷, –) to check the equation;

8 * 20 * 320 * 20 * 10 = 166

8 × 20 + 320 ÷ 20 - 10 = 166

On solving L.H.S we get;

→ 166 = 166 (correct)

As we get the correct answer we don’t need to check further.

Hence, option (2) is the correct answer.

8 × 9 ÷ 15 + 30 – 5 = 63

When the two signs interchanged the equation becomes;

(1). 8 - 9 ÷ 15 + 30 × 5 = 63

On solving L.H.S;

→ 157.4 = 63

So, L.H.S ≠ R.H.S (incorrect)

(2). 8 × 9 ÷ 15 - 30 + 5 = 63

On solving L.H.S;

→ -20.2 = 63

So, L.H.S ≠ R.H.S (incorrect)

(3). 8 + 9 ÷ 15 × 30 – 5 = 63

On solving L.H.S;

→ 21 = 63

So, L.H.S ≠ R.H.S (incorrect)

(4). 8 × 9 - 15 + 30 ÷ 5 = 63

On solving L.H.S;

→ 63 = 63

So, L.H.S = R.H.S (correct)

Hence, option (4) is the correct answer.