RRB NTPC CBT-1 previous year question
The mean proportional between 12 and a number is twice the mean proportional between 9 and 16. Find the number.
Asked in RRB NTPC 2026 — 14 June Shift 2 · Quantitative Aptitude
Tap an option to check your answer.
Show answer and explanation
Correct answer: (C) 48
Mean proportional between 9 and 16 is sqrt(9*16)=12, so twice that is 24. Setting sqrt(12x)=24 gives 12x=576, so x=48.
हिंदी में प्रश्न
12 और किसी संख्या के बीच का माध्यानुपाती, 9 और 16 के बीच के माध्यानुपाता का दांगुना है। वह सख्या ज्ञात PITT
उत्तर जाँचने के लिए किसी विकल्प पर टैप करें।
उत्तर और व्याख्या देखें
सही उत्तर: (C) 48
9 और 16 के बीच माध्यानुपाती sqrt(9*16)=12 है, इसका दोगुना 24 है। sqrt(12x)=24 रखने पर 12x=576 मिलता है, अतः x=48 है।
More solved Quantitative Aptitude questions
- Find the mean of the following data. Class interval0-88-1616-2424-3232-4040-48 Frequency 4 6 7 3 12 8
- The largest four-digit number which when divided by 10, 11 and 8 leaves remainder 7 in each case is:
- The measure of an interior angle of a regular polygon is 162°. Find the number of sides of the polygon.
- A shopkeeper sells two types of pens, A and B. The total number of pens sold in a day is 120. The price of pen A is ₹12 each and pen B is…
- Two banks, A and B, offered loans at 3.5% and 6.5% per annum, respectively. Ajay borrowed an amount of ₹2,60,000 from each bank. Find the…
- Two friends, P and Q, started a business by investing ₹2,300 and ₹4,600, respectively. At the end of one year, the business earned a total…