Ratio, Proportion, Indices, LogarithmMCQMTP June 22Question 913 of 302
All Questions

If (25)150=(25x)50\displaystyle (25)^{150} = (25x)^{50}, then the value of x\displaystyle x will be:

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

Correct Answer

✅ Option b — 54\displaystyle 5^4

All Options:

  • A53\displaystyle 5^3
  • B54\displaystyle 5^4
  • C52\displaystyle 5^2
  • D5\displaystyle 5

Detailed Solution & Explanation

We are given the equation:
(25)150=(25x)50\left( 25 \right)^{150} = \left( 25x \right)^{50}

To isolate the term with x\displaystyle x, let us raise both sides of the equation to the power of 150\displaystyle 150\displaystyle \frac{1}{50}:
[(25)150]150=[(25x)50]150\left[ \left( 25 \right)^{150} \right]^{150\displaystyle \frac{1}{50}} = \left[ \left( 25x \right)^{50} \right]^{150\displaystyle \frac{1}{50}}
Applying the exponent law (ab)c=abc\displaystyle \left(a^b\right)^c = a^{bc}:
2515050=25x25^{15050\displaystyle \frac{150}{50}} = 25x
253=25x25^3 = 25x

Dividing both sides of the equation by $25\displaystyle :<br><span class="katex-display"><span class="katex"><span class="katex-mathml"><math xmlns="http://www.w3.org/1998/Math/MathML" display="block"><semantics><mrow><mi>x</mi><mo>=</mo><mfrac><msup><mn>25</mn><mn>3</mn></msup><mn>25</mn></mfrac><mo>=</mo><msup><mn>25</mn><mn>2</mn></msup></mrow><annotation encoding="application/x-tex">x = 25325=252\displaystyle \frac{25^3}{25} = 25^2</annotation></semantics></math></span><span class="katex-html" aria-hidden="true"><span class="base"><span class="strut" style="height:0.4306em;"></span><span class="mord mathnormal">x</span><span class="mspace" style="margin-right:0.2778em;"></span><span class="mrel">=</span><span class="mspace" style="margin-right:0.2778em;"></span></span><span class="base"><span class="strut" style="height:2.1771em;vertical-align:-0.686em;"></span><span class="mord"><span class="mopen nulldelimiter"></span><span class="mfrac"><span class="vlist-t vlist-t2"><span class="vlist-r"><span class="vlist" style="height:1.4911em;"><span style="top:-2.314em;"><span class="pstrut" style="height:3em;"></span><span class="mord"><span class="mord">25</span></span></span><span style="top:-3.23em;"><span class="pstrut" style="height:3em;"></span><span class="frac-line" style="border-bottom-width:0.04em;"></span></span><span style="top:-3.677em;"><span class="pstrut" style="height:3em;"></span><span class="mord"><span class="mord">2</span><span class="mord"><span class="mord">5</span><span class="msupsub"><span class="vlist-t"><span class="vlist-r"><span class="vlist" style="height:0.8141em;"><span style="top:-3.063em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mtight">3</span></span></span></span></span></span></span></span></span></span></span><span class="vlist-s">​</span></span><span class="vlist-r"><span class="vlist" style="height:0.686em;"><span></span></span></span></span></span><span class="mclose nulldelimiter"></span></span><span class="mspace" style="margin-right:0.2778em;"></span><span class="mrel">=</span><span class="mspace" style="margin-right:0.2778em;"></span></span><span class="base"><span class="strut" style="height:0.8641em;"></span><span class="mord">2</span><span class="mord"><span class="mord">5</span><span class="msupsub"><span class="vlist-t"><span class="vlist-r"><span class="vlist" style="height:0.8641em;"><span style="top:-3.113em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mtight">2</span></span></span></span></span></span></span></span></span></span></span></span><br><br>We know that &#36;25 = 5^2. Let us express x\displaystyle x with a base of 5\displaystyle 5:
x=(52)2=52×2=54x = \left( 5^2 \right)^2 = 5^{2 ×\displaystyle \times 2} = 5^4

Hence, **Option B** is the correct answer.

About This Chapter: Ratio, Proportion, Indices, Logarithm

Paper

Paper 3: Quantitative Aptitude

Weightage

5-7 Marks

Key Topics

Ratio, Proportion, Indices, Logarithms

This chapter covers Ratio, Proportion, Indices, Logarithms and is part of Paper 3: Quantitative Aptitude in the CA Foundation exam.

View Official ICAI Syllabus

Exam Strategy Tip

This topic carries 5-7 Marks weightage. Focus on understanding core concepts rather than memorizing.

More Questions from Ratio, Proportion, Indices, Logarithm

Ready to Master Ratio, Proportion, Indices, Logarithm?

Practice all 302 questions with instant feedback, earn XP, track your streaks, and ace your CA Foundation exam.

Start Practicing — It's Free