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Category: Probability and Statistics

For-the-random-variable-x-show-that-a-Var-x-E-2-x-E-x-2-b-Var-ax-b-a-2-Var-x-

Question Number 50855 by peter frank last updated on 21/Dec/18 $${F}\mathrm{or}\:{the}\:{random}\:{variable} \\ $$$${x}\:{show}\:{that} \\ $$$$\left.{a}\right){Var}\left({x}\right)={E}^{\mathrm{2}} \left({x}\right)−\left[{E}\left({x}\right)\right]^{\mathrm{2}} \\ $$$$\left.{b}\right){Var}\left({ax}+{b}\right)={a}^{\mathrm{2}} {Var}\left({x}\right) \\ $$$$ \\ $$ Answered by…

the-distirbution-function-for-a-random-variable-X-is-F-x-1-2e-2x-x-0-0-x-lt-0-find-1-the-density-function-f-x-2-p-x-gt-2-3-p-3-lt-x-4-

Question Number 181677 by ali009 last updated on 28/Nov/22 $$\:{the}\:{distirbution}\:{function}\:{for}\:{a}\:{random} \\ $$$${variable}\:{X}\:{is} \\ $$$${F}\left({x}\right)=\begin{cases}{\mathrm{1}−\mathrm{2}{e}^{−\mathrm{2}{x}} \:\:\:\:\:\:\:\:\:\:\:\:\:\:{x}\geqslant\mathrm{0}}\\{\mathrm{0}\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:{x}<\mathrm{0}}\end{cases} \\ $$$${find} \\ $$$$\left.\mathrm{1}\right){the}\:{density}\:{function}\:{f}\left({x}\right) \\ $$$$\left.\mathrm{2}\right){p}\left({x}>\mathrm{2}\right) \\ $$$$\left.\mathrm{3}\right){p}\left(−\mathrm{3}<{x}\leqslant\mathrm{4}\right) \\ $$…

Given-X-Uniform-0-and-Uniform-20-40-Find-the-cdf-of-X-F-X-x-for-x-0-20-and-x-20-40-

Question Number 116083 by Joel574 last updated on 30/Sep/20 $$\mathrm{Given}\:{X}\:\mid\:\Theta=\theta\:\backsim\:{Uniform}\left(\mathrm{0},\theta\right)\:\mathrm{and}\: \\ $$$$\Theta\:\backsim\:{Uniform}\left(\mathrm{20},\mathrm{40}\right). \\ $$$$\mathrm{Find}\:\mathrm{the}\:\mathrm{cdf}\:\mathrm{of}\:{X},\:\:{F}_{{X}} \left({x}\right)\:\mathrm{for}\:{x}\in\left[\mathrm{0},\mathrm{20}\right)\:\mathrm{and}\:{x}\in\left[\mathrm{20},\mathrm{40}\right) \\ $$ Terms of Service Privacy Policy Contact: info@tinkutara.com

If-Mike-has-10-blocks-numbered-from-1-through-to-10-What-is-the-probability-that-he-didn-t-choose-a-block-number-7-

Question Number 115898 by bemath last updated on 29/Sep/20 $${If}\:{Mike}\:{has}\:\mathrm{10}\:{blocks}\:{numbered} \\ $$$${from}\:\mathrm{1}\:{through}\:{to}\:\mathrm{10}\:.\:{What}\:{is}\:{the} \\ $$$${probability}\:{that}\:{he}\:{didn}'{t}\:{choose} \\ $$$${a}\:{block}\:{number}\:\mathrm{7}? \\ $$ Answered by TANMAY PANACEA last updated on…

I-watch-a-favorite-TV-program-daily-for-30-min-If-there-were-ads-every-3-hours-what-s-the-probability-that-i-will-see-ads-once-again-the-next-day-while-watching-that-program-

Question Number 181140 by Acem last updated on 22/Nov/22 $${I}\:{watch}\:{a}\:{favorite}\:{TV}\:{program}\:{daily}\:{for}\:\mathrm{30}\:{min}. \\ $$$$\:{If}\:{there}\:{were}\:{ads}\:{every}\:\mathrm{3}\:{hours},\:{what}'{s}\:{the} \\ $$$$\:{probability}\:{that}\:{i}\:{will}\:{see}\:{ads}\:{once}\:{again}\:{the}\:{next} \\ $$$$\:{day}\:{while}\:{watching}\:{that}\:{program}? \\ $$$$ \\ $$ Commented by mr W last…

2-blondes-hair-of-6-girls-will-sit-around-a-circular-table-what-s-the-probability-that-those-two-girls-sitting-next-to-each-other-

Question Number 180990 by Acem last updated on 20/Nov/22 $$\mathrm{2}\:{blondes}\:{hair}\:{of}\:\mathrm{6}\:{girls}\:{will}\:{sit}\:{around}\:{a}\:{circular} \\ $$$$\:{table},\:{what}'{s}\:{the}\:{probability}\:{that}\:{those}\:{two}\:{girls} \\ $$$$\:{sitting}\:{next}\:{to}\:{each}\:{other}? \\ $$ Answered by mr W last updated on 20/Nov/22 $${p}=\frac{\mathrm{4}!\mathrm{2}!}{\mathrm{5}!}=\frac{\mathrm{48}}{\mathrm{120}}=\frac{\mathrm{2}}{\mathrm{5}}=\mathrm{40\%}…