Theoretical DistributionsMTP March 22Question 3987 of 230
All Questions

What is the mean of X having the following density function? f(x)=142πe(x10)232\displaystyle f(x) = \frac{1}{4\sqrt{2\pi}} e^{-\frac{(x-10)^2}{32}} for <x<\displaystyle -\infty < x < \infty

Options

A10
B4
C40
DNone of these
For any discrepancies in this question, email contact@cadada.in

Correct Answer

Option a10

All Options:

  • A10
  • B4
  • C40
  • DNone of these

Detailed Solution & Explanation

**Mean from Normal Probability Density Function** The standard probability density function (pdf) of a normal random variable X\displaystyle X is: f(x)=frac1sigmasqrt2piefrac(xmu)22sigma2f(x) = \\frac{1}{\\sigma\\sqrt{2\\pi}} e^{-\\frac{(x-\\mu)^2}{2\\sigma^2}} Comparing the given function: f(x)=frac14sqrt2piefrac(x10)232f(x) = \\frac{1}{4\\sqrt{2\\pi}} e^{-\\frac{(x-10)^2}{32}} with the standard form: 1. **From the exponent term:** frac(x10)232=frac(xmu)22sigma2-\\frac{(x-10)^2}{32} = -\\frac{(x-\\mu)^2}{2\\sigma^2} This directly gives the mean: mu=10\\mu = 10 And the variance term: 2sigma2=32impliessigma2=16impliessigma=42\\sigma^2 = 32 \\implies \\sigma^2 = 16 \\implies \\sigma = 4 2. **From the constant coefficient:** frac1sigmasqrt2pi=frac14sqrt2piimpliessigma=4\\frac{1}{\\sigma\\sqrt{2\\pi}} = \\frac{1}{4\\sqrt{2\\pi}} \\implies \\sigma = 4 This is consistent with the standard deviation derived from the exponent. Thus, the mean (mu\displaystyle \\mu) of the distribution is 10\displaystyle 10, which corresponds to Option A. Hence, **Option A** is the correct answer.

About This Chapter: Theoretical Distributions

Paper

Paper 3: Quantitative Aptitude

Weightage

4-6 Marks

Key Topics

Binomial, Poisson, Normal Distribution

This chapter covers Binomial, Poisson, Normal Distribution 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 Theoretical Distributions

Ready to Master Theoretical Distributions?

Practice all 230 questions with instant feedback, earn XP, track your streaks, and ace your CA Foundation exam.

Start Practicing — It's Free