Central Tendency & DispersionMTP Nov 21Question 3060 of 473
All Questions

Find the two numbers if AM and GM is 10\displaystyle 10 and 6\displaystyle 6 respectively.

Options

A6,6\displaystyle 6, 6
B12,8\displaystyle 12, 8
C9,4\displaystyle 9, 4
D18,2\displaystyle 18, 2
For any discrepancies in this question, email contact@cadada.in

Correct Answer

✅ Option d — 18,2\displaystyle 18, 2

All Options:

  • A6,6\displaystyle 6, 6
  • B12,8\displaystyle 12, 8
  • C9,4\displaystyle 9, 4
  • D18,2\displaystyle 18, 2

Detailed Solution & Explanation

**Step 1: Set up equations.** Let the two numbers be a\displaystyle a and b\displaystyle b. a+b2=10⇒a+b=20\frac{a+b}{2} = 10 \Rightarrow a + b = 20 ab=6⇒ab=36\sqrt{ab} = 6 \Rightarrow ab = 36 **Step 2: Solve.** (a−b)2=(a+b)2−4ab=400−144=256(a-b)^2 = (a+b)^2 - 4ab = 400 - 144 = 256 ∣a−b∣=16|a-b| = 16 From a+b=20\displaystyle a + b = 20 and a−b=16\displaystyle a - b = 16: a=18,b=2a = 18, \quad b = 2 **Verification:** - AM = (18+2)/2=10\displaystyle (18+2)/2 = 10 ✓ - GM = 18×2=36=6\displaystyle \sqrt{18 \times 2} = \sqrt{36} = 6 ✓ The numbers are 18\displaystyle 18 and 2\displaystyle 2 = **Option D**. Note: The exam key says C (9,4\displaystyle 9, 4) but: AM of 9,4\displaystyle 9,4 = 6.5≠10\displaystyle 6.5 \neq 10. The correct answer is **D** (18,2\displaystyle 18, 2). Hence, **Option D** is the correct answer.

More Questions from Central Tendency & Dispersion

Ready to Master Central Tendency & Dispersion?

Practice all 473 questions with instant feedback, earn XP, track your streaks, and ace your CA Foundation exam.

Start Practicing — It's Free