Select the option that can replace both the instances of ' * ' in the following equation to make it correct. ≤ft(*/21) × ≤ft(*/189) = 1 - Quantitative Aptitude MCQ Competitive Exam Practice 2026 | ExamTest.live

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Select the option that can replace both the instances of ' *' in the following equation to make it correct. (\frac{*}{21}) \times (\frac{*}{189}) = 1

Solution & Step-by-step Explanation

Let the symbol * be represented by x : \frac{x}{21} \times \frac{x}{189} = 1 \frac{x ^{2}}{21 \times 189} = 1 x^{2} = 21 \times 189 Factorizing the terms: x^{2} = 21 \times (21 \times 9) x^{2} = 2 1^{2} \times 3^{2} x = 2 1^{2} \times 3^{2} = 21 \times 3 = 63

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Select the option that can replace both the instances of ' *' in the following equation to make it correct. (\frac{*}{21}) \times (\frac{*}{189}) = 1

63

147

21

48

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