# Dhamnekar Win,odd

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131

1. ## How many points the chess tournament player will get by winning a game or by making a game draw?

In a chess tournament, each participant plays with every other participant exactly once. Each participant gets 1 point for a winning a game, 0.5 points for a draw and no point for a loosing a game. At most, how many of the 40 participants can score 24 points or more? My attempt to answer this question: There will be $\binom{40}{2}=780$ games in this chess tournament. Now each player will play 39 game. The probability of winning a game is $\frac13$. Probability of loosing a game is $\frac13$ and the probability of making a game draw is $\frac13$. So, out of 780 games, 260 games will be won by some players, 260 games will be lost and 260 games will be drawn. How can we proceed from here to answer this question?
2. ## How can I use the Stokes Theorem to answer these questions?

$\displaystyle\int\limits_C xydx + (z-x)dy + 2yzdz = 0-2+8=6$
3. ## How can I use the Stokes Theorem to answer these questions?

Calculate the line integral of the vecor field f(x,y,z) along the curve C $\left(\displaystyle\int\limits_C f \cdot dr\right)$ 1)f(x,y,z) = yzi + xzj + xyk; C : the polygonal path from (0,0,0) to (1,0,0) to ( 1,2,0). 2)f(x,y,z) = xyi + (z-x)j + 2yzk; C : the polygonal path from (0,0,0) to (1,0,0) to (1,2,0) to (1,2,-2). How can I use here Stokes theorem? My work to answer to both these questions is in progress. Any math help, clue, or even correct answers will be accepted.😇😀
4. ## Probability spaces

A circular target of unit radius is divided into four annular zones with outer radii 1/4, 1 /2, 3/4, and I, respectively. Suppose 10 shots are fired independently and at random into the target. (a) Compute the probability that at most three shots land in the zone bounded by the circles of radius 1 /2 and radius 1. (b) If 5 shots land inside the disk of radius 1 /2, find the probability that at least one is in the disk of radius 1 /4. My answers:(a) $\displaystyle\sum_{k=0}^{3}\binom{10}{k}(\frac34)^k (\frac14)^{10-k}$ (b)$\frac{\displaystyle\sum_{k=1}^{5}\binom{5}{k}(\frac{1}{16})^k(\frac{3}{16})^{5-k}}{\binom{10}{5}(\frac14)^5(\frac34)^5}=1.275e-2$ My answer to (a) is correct. Author's answer for (b) is $1- (\frac34)^5$ Whose answer is correct? My answer for (b) or author's answer for (b)?
5. ## What is the E° for the reaction Ti⁰ ⇌ Ti³⁺ + 3 e⁻ ?

It is sometimes necessary to compute E° for a given half reaction from other half reaction of known E°. For example, the standard electrode potential for the oxidation of Titanium metal to Ti³⁺ can be obtained from the following half reaction: Ti²⁺ + 2 e⁻ ⇌ Ti⁰ E° = -1.63 Volts ① Ti³⁺ + e⁻ ⇌ Ti²⁺ E° = -0.37 Volts ② Calculate E° for Ti⁰ ⇌ Ti³⁺ + 3 e⁻ My answer: ② is more spontaneous reaction than ①. Reduction: Ti³⁺ + e⁻ ⇌ Ti²⁺ E° = -0.37 Volts ; Oxidation: Ti²⁺ + 2 e⁻ ⇌ Ti⁰ E° = -1.63 Volts Hence, E∘rx=E∘red−E∘ox=−0.37V−(−1.63V)=+1.26VErx∘=Ered∘−Eox∘=−0.37V−(−1.63V)=+1.26V My answer matches with author's answer. But, Is my logic in answering this question correct?
6. ## Conditional probability of making a claim by an automobile insurance policy holder

Is the above intuitive explanation of "why the inequality $P(A_2|A_1) > P(A_1)$ is true" correct?
7. ## Probability of misprints on each page

My answer to (a) N= Total symbols on each page. r= 50 misprints. So, what is impossible is two or more misprints occurring in the same symbol. So, first condition of Fermi-Dirac statistics is satisfied. All distinguishable arrangements satisfying the first condition have equal probabilities. In our case, It is $\binom{500N}{50}^{-1}$
8. ## Coin flipping problem (Markov chain)

Suppose that coin 1 has probability 0.7 of coming up heads, and coin 2 has probability 0.6 of coming up heads. If the coin flipped today comes up heads, then we select coin 1 to flip tomorrow, and if it comes up tails, then we select coin 2 to flip tomorrow. If the coin initially flipped is equally likely to be coin 1 or coin 2, then a)what is the probability that the coin flipped on the third day after the initial flip is coin 1? b)Suppose that the coin flipped on Monday comes up heads. What is the probability that the coin flipped on Friday of the same week also comes up heads? My attempt to answer this question:
9. ## How to prove this corollary in line integral?

If f is in the direction of r'(t) then it is in the direction of increasing r(t). So, the directions of f(t) and r'(t) will also be same. Definition of dot product: And ds =|| r'(t)|| ⇒ $\sqrt{x'(t)^2 + y'(t)^2}dt$ so, work = force × distance = $\displaystyle\int_C f\cdot dr= \displaystyle\int_C \left\vert\vert{f} \right\vert\vert ds$
10. ## How to prove this corollary in line integral?

. Show that if f points in the same direction as r'(t) at each point r(t) along a smooth curve C, then $\displaystyle\int_C f\cdot dr = \displaystyle\int_C ||f|| ds ?$ How can I prove this corollary in line integral?
11. ## Using line integral to find the lateral surface area of some part of a cylinder

I got the answer to this question. I computed it as follows: $\displaystyle\int_0^{2\pi} 12 dt = 24\pi$
12. ## Using line integral to find the lateral surface area of some part of a cylinder

Use a line integral to find the lateral surface area of the part of the cylinder $x^2 +y^2 =4$ below the plane x + 2y + z =6 and above the xy-plane. How to answer this question? What is the answer of this question? Graph of the required lateral surface area of the cylinder is given below:
13. ## Derivation of P.D.F. from distribution function

I tag this question as 'SOLVED'. Author's computations are correct. Thank you.
14. ## Derivation of P.D.F. from distribution function

After studying these author's computations, I understood the differentiation part but I don't understand cancellation part and final term computation.
15. ## Derivation of P.D.F. from distribution function

Author computed $F_{X_k} (x)$ as follows. but I don't understand it. Would any member explain me the following computations?

18. ## Finding the volume of the solid using change of variables technique

Answers to all of the aforesaid questions are affirmative.
19. ## Finding the volume of the solid using change of variables technique

I think my answer in the original post is incorrect. So, I want to correct it. My corrected answer is $\displaystyle\int_0^{2\pi}\displaystyle\int_0^2\displaystyle\int_0^4 r dz dr d\theta =16\pi$ Is this answer correct?
20. ## Finding the volume of the solid using change of variables technique

Find the volume of the solid bounded by $z = x^2 + y^2$ and $z^2 = 4(x^2 + y^2)$ My attempt to answer this question: $\displaystyle\int_0^{2\pi}\displaystyle\int_0^2\displaystyle\int_0^4 1 \rho^2 \sin{(\phi)} d\rho d\phi d\theta = -\frac{128\pi \cos{(2)}- 128\pi}{3}= 189.822143919$ Is this answer correct?
21. ## How to use the change of variables technique here?

I computed the volume inside both the sphere $x^2 + y^2 + z^2 =1$ and cone $z= \sqrt{x^2 + y^2}$ as follows: $\displaystyle\int_0^{2\pi} \displaystyle\int_0^{\frac{\pi}{4}}\displaystyle\int_0^1 \rho^2 \sin{\phi}d\rho d\phi d\theta= 0.61343412301 =\frac{(2-\sqrt{2})\pi}{3}$. This answer is correct.
22. ## How to use the change of variables technique here?

I want to correct the volume asked in the question computed by me = $\frac{\pi}{3} \times \frac12 \times \frac{1}{\sqrt{2}} + \frac{\pi}{3} \times (1-\frac{1}{\sqrt{2}})^2 \times (\frac{3}{\sqrt{2}} -(1-\frac{1}{\sqrt{2}}))=0.534497630798$
23. ## How to use the change of variables technique here?

My attempt: I graphed the cone inside the sphere as in my first post. But I don't understand how to use the change of variables technique here to find the required volume. My answer without using integrals is volume of the cone + volume of the spherical cap = Is this answer correct? If correct, how to derive this answer using integration technique?
24. ## How to use the change of variables technique here?

Find the volume V inside both the sphere x2 + y2 + z2 = 1 and the cone z = $\sqrt{x^2+ y^2}$ How to use change of variables technique in this problem?
25. ## C program could not be executed at Windows command prompt

Yes. From that point of view, this program is wrong. But we already decided to ignore the leap year and we mentioned that as the comment.
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