Birthday Present
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Math Forum: Ask Dr. Math FAQ: The Birthday Problem -- Ask Dr. Math: FAQ The Birthday Problem Dr. Math FAQ || Classic Problems || Formulas || Search Dr. Math || Dr. Math Home Suppose you flip a coin and bet that it will come up tails. Since you are equally likely to get heads or tails, the probability of tails is 50%. This means that if you try this bet often, you should win about half the time. What if somebody offered to bet that at least two people in your math class had the same birthday? Would you take the bet? This question is more complicated than flipping a coin, because the chance of finding two people with the same birthday depends on the number of people you ask. If there were only one other person in your math class, you might be surprised to find out that she had the same birthday as you. If there were a pair of people with the same birthday in a class of 366 people, would you still be surprised? How large must a class be to make the probability of finding two people with the same birthday at least 50%? Let's forget about leap year when we solve this problem (no February 29 birthdays!) This way, we can assume that a year is always 365 days long. We'll start by figuring out the probability that two people have the same birthday. The first person can have any birthday. That gives him 365 possible birthdays out of 365 days, so the probability of the first person having the "right" birthday is 365/365, or 100%. The chance that the second person has the same birthday is 1/365. To find the probability that both people have this birthday, we have to multiply their separate probabilities. (365/365) * (1/365) = 1/365, or about 0.27%. Now, what about three people ? The chance of the first and second person sharing a birthday is still 1/365. The first and third person might share a birthday instead. The probability of that is 1/365 as well. But what if the second and third person shared a birthday? And what if all three of them had the same birthday? Things are getting complicated fast. Four or five people would be even messier. Is there a simpler way? To solve the birthday problem, we need to use one of the basic rules of probability: the sum of the probability that an event will happen and the probability that the event won't happen is always 1. (In other words, the chance that anything might or might nothappen is always 100%.) If we can work out the probability that no two people will have the same birthday, we can use this rule to find the probability that two people will share a birthday: P(event happens) + P(event doesn't happen) = 1 P(two people share birthday) + P(no two people share birthday) = 1 P(two people share birthday) = 1 - P(no two people share birthday). So, what is the probability that no two people will share a birthday? Again, the first person can have any birthday. The second person's birthday has to be different. There are 364 different days to choose from, so the chance that two people have different birthdays is 364/365. That leaves 363 birthdays out of 365 open for the third person. To find the probability that both the second person and the third person will have different birthdays, we have to multiply: (365/365) * (364/365) * (363/365) = 132 132/133 225, which is about 99.18%. If we want to know the probability that four people will all have different birthdays, we multiply again: (364/365) * (363/365) * (362/365) = 47 831 784/ 48 627 125, or about 98.36%. We can keep on going the same way as long as we want. A formula for the probability that n people have different birthdays is ((365-1)/365) * ((365-2)/365) * ((365-3)/365) * . . . * ((365-n+1)/365). If you know permutation notation, you can write this formula as (365_P_n)/(365^n). That's the same as 365! / ((365-n)! * 365^n). We've made some progress, but we still haven't answered the original question: how large must a class be to make the probability of finding two people with the same birthday at least 50%? We know that the probability of finding at least two people with the same birthday is 1 minus the probability that everybody has a different birthday, and we know how to find the probability that everybody has a different birthday for any number of people. The easiest way to find the right class size is to use a calculator to try different numbers in the formula. It turns out that the smallest class where the chance of finding two people with the same birthday is more than 50% is... a class of 23 people . (The probability is about 50.73%.) From the Dr. Math archives: Probability Theory: Coincidental Birthday Probability of the Same Birthday within a Group Birthday Probabilities Three Share a Birthday The Birthday Problem; Queuing at a Bank Birthday Probability, Class of 25 One Person of Seven Born on Monday Odds of Left-Handedness in a Group From the Web: The Birthday Problem: A short lesson in probability , George Reese A Java applet that you can use to test different class sizes (it works better with small classes) and graphs of the probability for different numbers of people. The Law of Small Errors , Keith Devlin The birthday problem, and related questions - what's the probability that someone will have your birthday? Birthday Surprises, Ivars Peterson Birthday Problem, Eric Weisstein's World of Mathematics Coincidence, Alexander Bogomolny How to Read Mathematics, Shai Simonson and Fernando Gouveau This article uses an explanation of the birthday problem as an example. An Introduction to Mathematica and the "Birthday Problem," Louie Beuschlein For a general review of probability: Probability, Dr. Math FAQ Probability in the Real World, Dr. Math FAQ - Ursula Whitcher, for the Math Forum Submit your ownquestion to Dr. Math [ Privacy Policy ] [ Terms of Use ] Math Forum Home || Math Library || Quick Reference || Math Forum Search Ask Dr. Math ® © 1994-2005 The Math Forum http://mathforum.org/dr.math/
Gifts For Men Articles
Thank You Gifts For Men - Gifts BW gifts | gifts Resources | Add URL Wine Gifts & Baskets From the casual wine drinker to the serious enthusiast, we have a gift that will make them smile. Our selection includes premium wine, gourmet baskets, distinctive champagne sets & the very finest California and Northwest wines. Thank You Gifts For Men Articles Veterans' Memorial Museum in Huntsville Glimpses inside the new Veterans' Memorial Museum on Airport Road in Huntsville is our Huntsville Picture of the Week....( Continue Reading ) Now We Can Begin Crystal Eastman, socialist feminist, writes in 1920 about the tasks that remain after the vote was won....( Continue Reading ) Pericles - Shakespeare's Plays Shakespeare's play Pericles, from your About.com Guide...( Continue Reading ) Best Books of the Year-Women's Health-12/03/98 Great gifts for the holidays for the special people in your life. from your About.com Guide...( Continue Reading ) How To Be an 80s Funk Star? A silly and a simple how to on look like an 80s funk star....( Continue Reading ) Thank You Gifts For Men Directory Links cool anniversary gifts birthday gifts india christian spiritual gifts christmas gifts for bosses cat lovers gifts unique groomsmen gifts cheap homemade christmas gifts wedding aniversary gifts by year homemade anniversary gifts unique mothers day gifts fathers day gifts great gifts for him 6 month anniversary gifts inexpensive christmas gifts to make birthday gift baskets gift baskets washington anniversary gifts by the year sears com gifts online valentine gifts 2nd anniversary gifts fifth anniversary gifts gift baskets in california baby showers gifts college student gifts handmade mothers day gifts gift fruit baskets monogramed baby gifts graduation gifts college anniversary gifts per year birthday gifts for mom anniversary gifts paper wedding anniversary gifts year personalized mothers day gifts bachelorette party gifts easter gifts online wedding gifts for groom one year wedding anniversary gifts personalised business gifts gift baskets of maryland anniversary gifts 10 year gifts golf gift baskets rhode island irish baby gifts gifts for young girls keepsake baby gifts Popular Search Terms: Gifts BW © 2004 Gifts BW All trademarks are the property of their respective owners. All Rights Reserved. This site is not related to Brajeshwar or Brajeshwar.com in anyway, shape or form
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Gift Baskets and Wine Basket Gifts by Wine Country Gift Baskets -- search: click here for advanced search Welcome Guest ACCOUNT SIGN IN ORDER STATUS SHOPPING BASKET Mothers Day -- Free Shipping Online Specials Gourmet Food Gift Baskets Wine Gift Baskets Gift Towers Theme Baskets Candle Gift Baskets -- Spa Gift Baskets Teddy Bear Baskets GHIRARDELLI Chocolate -- GODIVA Gift Baskets -- Wine Country's Private Cellar Wines By Family Kosher Gift Baskets -- Birthday Gift Baskets Coffee Gift Baskets Thank You Gifts Get Well Gift Baskets Sympathy Baskets Romance Gift Baskets Corporate Gifts New Baby Baskets Customer Service Catalog Request Corporate Sales Contact Us FAQ's Make Us Your Homepage Bookmark This Page Tell a Friend The #1 Gift Basket Website! Source:Alexa 5/2005 -- The Ritz Perfect for sharing, this large metal basket is generously filled with some of Wine Country's finest food. This deluxe assortme... $ 99.95 Pacific Heights Five individually boxed and beautifully wrapped surprises. Soft and chewy vanilla caramels, cranberry popcorn clusters, Belgian milk chocolate truffles, Mama Mell... $ 19.95 Crane Lake Duet Whether they prefer red or white wine, you can't miss with this terrific selection. Crane Lake Chardonnay and Cabernet Sauvignon are brought together w... $ 39.95 World of Thanks Express your gratitude with this fresh and enjoyable basket. Filled with Ghirardelli milk chocolate with almonds, Godiva milk chocolate hot cocoa, dried apr... $ 39.95 Spa Gift Baskets Wine Gift Baskets Corporate Gifts Gourmet Food Gift Baskets | | Wine Gift Baskets | | Gift Towers | | Theme Baskets | | Candle Baskets | | Spa Gift Baskets | | GHIRARDELLI Chocolate GODIVA Gift Baskets | | Wine Country's Private Cellar | | Wines By Family | | Online Specials | | Free Shipping Customer Service | | Catalog Request | | Corporate Sales | | Contact Us | | FAQ's | | Employment | | Links | | Site Map | | Privacy Policy 2005 Wine Country Gift Baskets. All rights reserved. (800) 324-2793 WCGB01
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Gifts Women - Gifts BW gifts | gifts Resources | Add URL Wine Gifts & Baskets From the casual wine drinker to the serious enthusiast, we have a gift that will make them smile. Our selection includes premium wine, gourmet baskets, distinctive champagne sets & the very finest California and Northwest wines. Gifts Women Articles Gifts for Women When buying gifts for women remember they like to feel that others are thoughtful enough to take the time to select a gift that was selected just for them. The best gifts for women will enrich their lives by pampering them, making them feel sexy or a...( Continue Reading ) Gifts for Women Looking for Valentine's Day gifts for women? Here are five suggestions to give the perfect gift this Valentine's day for the woman in your life....( Continue Reading ) Gifts for Women Unique gifts and tools for the kitchen, great cookbooks, gift baskets, and magazine subscriptions....( Continue Reading ) Arizona Gifts for Women Great Arizona gifts for the woman on your gift list. These gifts for women say "Arizona."...( Continue Reading ) Gifts for Women Unique gifts and tools for the kitchen, great cookbooks, gift baskets, and magazine subscriptions....( Continue Reading ) Gifts Women Directory Links thank you notes for gifts gifts for women police gifts to chennai christmas gifts for the family cellini fine gifts handmade gifts unique unusual gifts gifts for 14 year old boys gifts for pets gift baskets toronto 3rd wedding anniversary gifts gift baskets las vegas gift baskets hawaii gifts for wedding anniversaries valentine gifts get well gifts for kids virtual gifts second anniversary gifts golden wedding anniversary gifts baby gift baskets personalized corporate gifts personalized valentines gifts gift baskets delivery spiritual gifts bible study fifth anniversary gifts gifts for men on valentines day easter egg baskets year anniversary gifts homemade gifts for mom wedding attendant gifts baby gifts unique girlfriend birthday gifts paper anniversary gifts what are my spiritual gifts gifts for weddings royce craft baskets best electronic gifts perfect christmas gifts romantic gift baskets houston christian wedding gifts gifts to hyderabad anniversary gifts 5 year gifts for older men holiday gifts for mom gift baskets of wyoming Popular Search Terms: Gifts BW © 2004 Gifts BW All trademarks are the property of their respective owners. All Rights Reserved. This site is not related to Brajeshwar or Brajeshwar.com in anyway, shape or form
Creative Gift Wrapping TIPical
At Home : Table Settings / Decor : Creative Gift Wrapping : Home & Garden Television Program Guide Shows A - Z Decorating Remodeling Gardening At Home Crafts Store SEARCH AT HOME Antiques / Collectibles Books / Videos Cleaning Entertaining General Information Holidays / Special Occasions Outdoor Parties Table Settings / Decor Tips / Techniques Wine Other Hobbies / Interests Kids / Family Moneysaving Ideas Organizing Personal Care / Health Pets Real Estate Recipes Shopping Tips / Techniques Vacations / Travel Creative Gift Wrapping TIPical Mary Ellen : Episode TIP-1410 -- More Projects » Creative design expert Teri Stevens points out creative ways to wrap presents. Figure A Figure B Figure C Figure D Figure E Figure F Figure G Wrap the contents in three separate boxes, from biggest to smallest in yellow paper. Tie them together with yellow ribbon and top with red roses to create a beautiful tiered "wedding cake" (figure A) . Create a movie night in a basket. Place microwave popcorn, popcorn boxes, theater-style candy, videos or DVDs and a six-pack of soda in a large basket (figure B) . Add some curly ribbon with popcorn hot glued on to finish it off. Fill a jar with chocolate striped cookies (figure C) and marshmallows. Top with extendable skewers and a bow and you will have all the makings for s'mores. A baby shower gift, such as a cute baby outfit, can be put on a small teddy bear and finished off with a bow (figure D) . Wrap a bridal shower gift in towels and finish off with some pins. The towels are then part of the gift. Use contrasting towels, one for the wrapping and one for the bow. Make a bow out of another towel threaded through a measuring cup set ring and attach with chip clips (figure E) . A beautiful box doesn't need to be wrapped. Just top with a bow and fill the box with cards (figure F) . Take two tall kitchen bags, cut off the ends and tie with decorative hair clips (figure G) . This is great for when you are out of wrapping paper. ALSO IN THIS EPISODE: TIPical Mary Ellen : Episode TIP-1410 • Rosy Floral Rings • Kitchen Task Lighting 101 • Creative Gift Wrapping • Tip of the Day Home | About Us | Newsletters | Questions | Advertising Site Map | Privacy | Legal DIY | Fine Living | Food Network | Shop At Home Great American Country | HGTVPro | Living | Video On Demand Comparison Shop for Home Gifts & Patio Furniture at Shopzilla © 2005 Scripps Networks, Inc. All rights reserved.