EquationsMCQMTP Mar 22Question 1014 of 221
All Questions

A number consist of two digits. The digits in tens place is 3 times the digit in the unit's place. If 54 is subtracted from the digits are reversed. The number is

Chapter 2 Diagram

Select Your Answer (Keyboard: A, B, C, D)
For any discrepancies in this question, email contact@cadada.in

Correct Answer

✅ Option c — 93

All Options:

  • A39
  • B92
  • C93
  • D94

Detailed Solution & Explanation

Let the digit in the ten's place be x\displaystyle x and the digit in the unit's place be y\displaystyle y. According to the first condition: x=3y— (Equation 1)x = 3y \quad — (Equation 1)\displaystyle \text{--- (Equation 1)} The original two-digit number is $10x + y$. If 54 is subtracted from the number, the digits are reversed. The reversed number is $10y + x$. According to the second condition: (10x+y)−54=10y+x(10x + y) - 54 = 10y + x 9x−9y=549x - 9y = 54 x−y=6— (Equation 2)x - y = 6 \quad — (Equation 2)\displaystyle \text{--- (Equation 2)} Substitute Equation 1 (x=3y\displaystyle x = 3y) into Equation 2: 3y−y=63y - y = 6 2y=6  ⟹  y=32y = 6 \implies y = 3 Now find x\displaystyle x: x=3(3)=9x = 3(3) = 9 The original number is: 10x+y=10(9)+3=9310x + y = 10(9) + 3 = 93 *(Note: The input key of 'b' (92) is incorrect as 9≠3×2\displaystyle 9 ≠\displaystyle \neq 3 ×\displaystyle \times 2 and subtracting 54 from 92 gives 38, which is not the reverse of 92. The mathematically correct option is C.)* **Correct Option: (c)**

About This Chapter: Equations

Paper

Paper 3: Quantitative Aptitude

Weightage

4-6 Marks

Key Topics

Linear, Quadratic and Cubic Equations

This chapter covers Linear, Quadratic and Cubic Equations and is part of Paper 3: Quantitative Aptitude in the CA Foundation exam.

View Official ICAI Syllabus

Exam Strategy Tip

This topic carries 4-6 Marks weightage. Focus on understanding core concepts rather than memorizing.

More Questions from Equations

If 3x+y+2x−y=−1\displaystyle 3x+y+2x−y\displaystyle \frac{3}{x+y} + \frac{2}{x-y} = -1 and 1x+y−1x−y=43\displaystyle 1x+y−1x−y=43\displaystyle \frac{1}{x+y} - \frac{1}{x-y} = \frac{4}{3} then (x,y)\displaystyle (x, y) is:

2x+510+3x+1015=5\displaystyle \frac{2x+5}{10} + \frac{3x+10}{15} = 5, find x\displaystyle x

Find value of x2−10x+1\displaystyle x^2 - 10x + 1 if x=15−26\displaystyle x = 15−26\displaystyle \frac{1}{5-2\sqrt{6}}

The cost of 2\displaystyle 2 oranges and 3\displaystyle 3 apples is $28$. If the cost of an apple is doubled then the cost of $3orangesand\displaystyle oranges and5$ apples is $75$. The original cost of 7\displaystyle 7 oranges and 4\displaystyle 4 apples (in Rs) is:

In a multiple choice question paper consisting of $100questionsof\displaystyle questions of1\displaystyle mark each, a candidate gets $60\% marks. If the candidate attempted all questions and there was a penalty of $0.25$ marks for wrong answers is:

The values of x\displaystyle x and y\displaystyle y satisfying the equations 3x+y+2x−y=3\displaystyle 3x+y+2x−y=3\displaystyle \frac{3}{x+y} + \frac{2}{x-y} = 3 and 2x+y+3x−y=233\displaystyle 2x+y+3x−y=233\displaystyle \frac{2}{x+y} + \frac{3}{x-y} = \frac{23}{3} given by

Ready to Master Equations?

Practice all 221 questions with instant feedback, earn XP, track your streaks, and ace your CA Foundation exam.

Start Practicing — It's Free