Mathematical Operation (SSC REASONING) Part-2

Total Questions: 50

1. What will come in the place of the question mark (?) in the following equation, if '+' and'x' are interchanged and'÷' and '-' are interchanged?

15÷5+8- 4 x7 = ?

Correct Answer: (d) 12
Solution:Given :- 15÷5+8 - 4 x 7= ?
As per instruction given in the question,
after interchanging '+' and 'x', '÷' and '-'
we get.
15-5x 8÷4+7
15-5×2+7 ⇒ 22-10 = 12

2. Which two numbers should be interchanged to make the given equation correct?

52+44 - 38÷2+13 x 4 - 26 = 97
(Note: Interchange should be done of entire number and not individual digits of a given number)

Correct Answer: (b) 38 and 26
Solution:Given :-
52+ 44-38÷2+13x4-26 = 97
After going through all the options,
option b satisfied. After interchanging 38
and 26 we get,
52 +44-26÷2+13 x 4-38
52 +31 +52-38 ⇒ 104-7 = 97
L.H.S. = R.H.S

3. Which two signs should be interchanged to make the following equation mathematically correct?

15 × 14-8+12÷4 = 5

Correct Answer: (a) x and +
Solution:Given: 15×14-8+12÷4= 5
After checking all the options one by one,
option (a) is satisfied.
15+14-8x 12 ÷ 4=5
15+14- 24 = 5 ⇒ 29-24 = 5

4. Which two numbers should be interchanged to make the given equation correct?

(24+14-6) ÷2+18×3-20 = 40
(Note: Interchange should be done of entire number and not individual digits of a given number)

Correct Answer: (d) 14 and 18
Solution:Given: (24+ 14-6) ÷2+18 x
3-20 = 40
After checking all the options one by one,
option (d) is satisfied, We get.
(24 +18- 6) ÷ 2+14x3-20 = 40
L.H.S: (24+18-6) ÷2+ 14 x 3 - 20
= 36÷2+14x3-20
= 18 + 42-20 = 60-20 = 40
L.H.S = R.H.S

5. What will come in the place of '?' in the following equation if '+ and 'x' are interchanged and '-' and '÷' are interchanged?

100-4÷7 + 5 × 12 = ?

Correct Answer: (a) 2
Solution:Given: 100-4÷7+5x 12 = ?
As per the instructions given in question,
after interchanging '+' and 'x', '-'and'
we get.
100 ÷ 4-7×5+12
25-7x5+12 ⇒ 37-35 = 2

6. Which two numbers should be interchanged to make the following equation correct?

12 x 2-6×7+3 x 5 × 4+10 = 46
(Note: Interchange should be done of the entire number and not individual digits of a given number.)

Correct Answer: (b) 2 and 4
Solution:Given: 12×2-6×7+3×5x 4+ 10 = 46
By checking all the options one by one,
option (b) is satisfied, after changing the
number we get
L.H.S: 12×4-6×7+3x 5×2+10
48-42 + 30 + 10 ⇒ 88 - 42 = 46
L.H.S = R.H.S

7. What will come in place of the question mark (?) in the following equation if '+' and 'x' are interchanged and '-' and '÷' are interchanged?

14÷12- 2+2×16 = ?

Correct Answer: (a) 18
Solution:Given:- 14÷12-2+2x 16
As per given instruction after
interchanging '+' and 'x' and ' and '÷'we
get
14-12÷2×2+ 16
14-6x2+16⇒2+16= 18

8. Which of the following interchanges of signs would make the given equation correct?

57-19 × 18+9 ÷ 45 = 18

Correct Answer: (a) ÷ and -
Solution:Given :- 57 - 19 x 18+9÷45=18
After going through all the options,
option (a) satisfy. After interchanging '
and'-' we get
57÷19 x 18 +9-45
3 x 18+9-4554-45 +9 = 18
L.H.S. = R.H.S.

9. Select the correct combination of mathematical signs that can sequentially replace the * signs and balance the given equation.

12*3*4 = 6*8* 8

Correct Answer: (c) x, +, x, -
Solution:Given :- 12*3*4= 6*8*8
After going through all the options,
option c is satisfied.
12 x 3+4 = 6×8-8 ⇒ 40 = 40
L.H.S. = R.H.S.

10. Which two numbers should be interchanged to make the following equation correct?

(16÷4) x 6 +26 - 48+9×8 = 154
(Note: Interchange should be done of the entire number and not individual digits of a given number.)

Correct Answer: (b) 16 and 48
Solution:(16÷4) x 6 +26-48+ 9 x 8= 154
After checking options one by one,
numbers in option (b) satisfies the
equation.
After interchanging number as per option
(b) we get,
LHS = (48 ÷ 4) x 6 +26- 16 +9×8
= 12 x 6+10+ 72 = 72 + 82 = 154 = RHS