All Exams Test series for 1 year @ ₹349 only
Question

Which two signs should be interchanged to make the given equation correct? $67 - 84 \div 12 \times 5 + 31 = 71$

This question was previously asked in
SSC Selection Post 2020 Graduation Level Question Paper (14 Dec, 2020) (Shift 3)
The correct answer is
+ and -

Understanding the Equation Problem

The question asks us to identify which pair of mathematical signs needs to be swapped in the given equation to make it mathematically correct. The equation is:

$$67 - 84 \div 12 \times 5 + 31 = 71$$

To solve this, we need to test the given options by interchanging the specified signs and then evaluate the equation using the standard order of operations (BODMAS/PEMDAS):

  • Brackets / Parentheses
  • Orders / Exponents
  • Division and Multiplication (from left to right)
  • Addition and Subtraction (from left to right)

Evaluating the Original Equation

First, let's check the value of the equation as it is given:

$$67 - 84 \div 12 \times 5 + 31$$

  1. Division: $84 \div 12 = 7$
  2. Multiplication: $7 \times 5 = 35$
  3. Subtraction: $67 - 35 = 32$
  4. Addition: $32 + 31 = 63$

The original equation evaluates to 63, not 71. So, we need to interchange signs.

Testing the Interchange of '+' and '-'

The correct answer suggests interchanging the addition (+) and subtraction (-) signs. Let's apply this change to the equation:

Original Equation: $67 - 84 \div 12 \times 5 + 31 = 71$

After swapping '-' and '+': $67 + 84 \div 12 \times 5 - 31 = 71$

Now, let's evaluate this new equation using BODMAS/PEMDAS:

  1. Division: $84 \div 12 = 7$
  2. Multiplication: $7 \times 5 = 35$
  3. Addition: $67 + 35 = 102$
  4. Subtraction: $102 - 31 = 71$

The equation now correctly evaluates to 71.

Conclusion

By interchanging the addition (+) sign and the subtraction (-) sign, the equation $67 - 84 \div 12 \times 5 + 31 = 71$ becomes correct. Therefore, the signs '+' and '-' should be interchanged.

Was this answer helpful?

Similar Questions

  1. What will come in place of the question mark (?) in the following equation if '+' means 'x', 'x' means '-', '-' means '$\div$' and '$\div$' means '+'?
    $18 \div 4 + 3 \times 2 - 2 = ?$

  2. Which two numbers (not individual digits) should be interchanged to make the given equation correct?
    $56+ (11 \times 2) - (52 \div 4) + 16 = 76$

  3. What will come in the place of '?' in the following equation, if '+' and '-' are interchanged and also 'x' and '$\div$' are interchanged?
    $13 \div 8-96 \times 6+17=?$

  4. Which two numbers (not digits of the numbers), from amongst the given options, should be interchanged to make the given equation correct? 

    $12 \times 9 + 27 \div 3 - 5 = 60$

  5. Which two signs should be interchanged to make the given equation correct?
    $99 \div 33 - 6 + 48 \times 26 = 40$
  6.  If ‘A’ stands for ‘÷’, ‘B’ stands for ‘×’, ‘C’ stands for ‘+’ and ‘D’ stands for ‘−’, what will come in place of the question mark (?) in the following equation?
    36 B 17 D 59 C 224 A 7 = ? 

  7. What will come in place of the question mark (?) in the following equation, if ‘+’ and ‘–’ are interchanged and ‘×’ and ‘÷’ are interchanged?
    16 ÷ 6 + 12 × 3 – 6 = ?

  8. Which two signs should be interchanged to make the given equation correct?
    $36+8 \times 184-23\div10 = 90$

  9. Which two signs should be interchanged to make the given equation correct? 

    $152 + 8 \times 16 \div 9 - 4 = 309$

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

    (28 ÷ 4) - (15 x 3) + 48 = ?


Important Questions from Bodmas Rule

  1. If 2945 ÷ 19 – 11 × 5 = 29 + a, find the value of a.

  2. DIRECTIONS: What should come in place of the question mark (?) in the following question?

    3800 - 22 × 1968 ÷ 48 = ? × 7

  3. Solve: {7.88 × 2 + 2.4 × 5 - 242.4 ÷ 4 + [9.2 × 4 - 2.46 of 3 + (36.3 ÷ 3 - 1.42 × 2)]} 

  4. What will come in the place of question mark (?) in the given expression?

    (420 ÷ 12 × 35 + 452- 152) = ?2

  5. Evaluate: (13 × 8 - √81 × 6 + 1 ) ÷ (√49 + 72 - 18 × 2 + 19)

Need Expert Advice?
Upcoming Exams
SSC JHT
September 13, 2026
SSC Selection Post
September 16, 2026
SSC CGL
September 30, 2026
UPSSSC PET
October 23, 2026
Test Series
SSC Selection Post img
SSC
SSC Selection Post (Graduation) (Phase 12) 2025 Mock Test Series
489 Tests 5 Tests Free
5423 Attempts
4.8(310)
English, Hindi

Start Your Preparation with Prepp Mobile App

Download the app from Google Play & App Store
Download the app from Google Play & App Store
Prepp Mobile App