# You have to do a 45 minute presentation with no preparation right now. **URL:** \ **Category:** In My Humble Opinion\ **Created:** [September 28, 2017, 2:26pm UTC](https://boards.straightdope.com/t/you-have-to-do-a-45-minute-presentation-with-no-preparation-right-now/797521 "2017-09-28T14:26:16Z")\ **Posts on this page:** 11\ **Page:** 7
**Author:** ![RTFirefly](https://avatars.discourse-cdn.com/v4/letter/r/c77e96/32.png) [@RTFirefly](https://boards.straightdope.com/u/RTFirefly)\ **Post date:** [January 12, 2018, 2:08am UTC](https://boards.straightdope.com/t/you-have-to-do-a-45-minute-presentation-with-no-preparation-right-now/797521/121 "2018-01-12T02:08:24Z")
I was just helping the Firebug with his arithmetic homework, and it occurred to me that I could easily do a 45-minute presentation on arithmetic shortcuts, with a side of estimating techniques to know if your answer is in the right ballpark. He had to do 792 x 965. Estimation: that’s like 800 x 1000, only a little smaller. So you should expect an answer that’s less than 800,000, but not a lot less. If you get an answer that’s above 800K, you know it’s wrong. If you get an answer that’s nowhere close to 800K, you know it’s wrong. Always estimate, because a lot of the time when you’re figuring the exact answer, you’ll get an answer that, if you think about it, _can’t_ be right. You’ll look a lot less stupid if you can see that, even if you don’t know what the right answer really is. Getting the exact answer: always try to turn your problem into an equivalent but simpler problem. It can’t always be done, but it’s amazing how _often_ it can be done. Shortcut 1: 965 is just 35 less than 1000. So your problem is now 792,000 - 792 x 35. Shortcut 2: multiplying by 70 is easier than multiplying by 35. Double that side, cut the other in half. 792 x 35 = 396 x 70. Shortcut 3, like shortcut 1: That’s 400x70 - 4x70 = 28,000 - 280 = 27,720. So your answer is 792,000 - 27,720 = 764,280. Now this is just arithmetic, which if you’re not in elementary school and being tested on it, you can do with a calculator. But these underlying lessons apply broadly to life. There are lots of opportunities to know what ballpark your answer has to be in, so use them. And there are lots of opportunities in life to turn a hard challenge into a similar but much easier one. Yeah, I can do 45 minutes on that. ---
**Author:** ![Spice\_Weasel](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/spice_weasel/32/5435_2.png) [@Spice\_Weasel](https://boards.straightdope.com/u/Spice_Weasel)\ **Post date:** [January 12, 2018, 2:10am UTC](https://boards.straightdope.com/t/you-have-to-do-a-45-minute-presentation-with-no-preparation-right-now/797521/122 "2018-01-12T02:10:33Z")
Impromptu public speaking? For nearly an hour? I have the perfect subject. “45 Ways I’d Like You To Kill Me Right Now.” ---
**Author:** ![Ulfreida](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/ulfreida/32/8014_2.png) [@Ulfreida](https://boards.straightdope.com/u/Ulfreida)\ **Post date:** [January 12, 2018, 2:16am UTC](https://boards.straightdope.com/t/you-have-to-do-a-45-minute-presentation-with-no-preparation-right-now/797521/123 "2018-01-12T02:16:18Z")
> [@John\_Mace](#): > > Oh, fer chrissake, now I’m going to have that dream again tonight!!! :eek: No, that’s a 45 minute presentation without wearing anything below the waist, although you won’t notice this for awhile. ---
**Author:** ![Spice\_Weasel](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/spice_weasel/32/5435_2.png) [@Spice\_Weasel](https://boards.straightdope.com/u/Spice_Weasel)\ **Post date:** [January 12, 2018, 2:55am UTC](https://boards.straightdope.com/t/you-have-to-do-a-45-minute-presentation-with-no-preparation-right-now/797521/124 "2018-01-12T02:55:49Z")
I guess the real answer is “How to Write a Nonprofit Grant that Doesn’t Suck.” Lame. ---
**Author:** ![Quimby](https://avatars.discourse-cdn.com/v4/letter/q/22d042/32.png) [@Quimby](https://boards.straightdope.com/u/Quimby)\ **Post date:** [January 15, 2018, 10:21pm UTC](https://boards.straightdope.com/t/you-have-to-do-a-45-minute-presentation-with-no-preparation-right-now/797521/125 "2018-01-15T22:21:59Z")
> [@susan](#): > > This is absolutely my my idea of a good time. If it were a reality show, I’d apply. If anyone makes it into a TV show I want an Executive Producer Credit and my checks made out to CASH 🙂 ---
**Author:** ![Cartooniverse](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/cartooniverse/32/3084_2.png) [@Cartooniverse](https://boards.straightdope.com/u/Cartooniverse)\ **Post date:** [January 15, 2018, 10:36pm UTC](https://boards.straightdope.com/t/you-have-to-do-a-45-minute-presentation-with-no-preparation-right-now/797521/126 "2018-01-15T22:36:51Z")
> [@Quimby](#): > > If anyone makes it into a TV show I want an Executive Producer Credit and my checks made out to CASH 🙂 As Producer/ Director, I’ll be delighted to cut you in for a reasonable percentage of my fee. Reasonable, mind you. Don’t go getting all D.G.A. on me. 😉 Sent from my SM-N910V using Tapatalk ---
**Author:** ![What\_Exit](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/what_exit/32/10652_2.png) [@What\_Exit](https://boards.straightdope.com/u/What_Exit)\ **Post date:** [January 15, 2018, 10:37pm UTC](https://boards.straightdope.com/t/you-have-to-do-a-45-minute-presentation-with-no-preparation-right-now/797521/127 "2018-01-15T22:37:01Z")
> [@Spice\_Weasel](#): > > I guess the real answer is “How to Write a Nonprofit Grant that Doesn’t Suck.” > > Lame. Actually that is a rare skill, I speak as someone that served on the board of a non-profit for about 10 years. I wish we had more people that could write grants. I sure can’t. ---
**Author:** ![Scougs](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/scougs/32/3158_2.png) [@Scougs](https://boards.straightdope.com/u/Scougs)\ **Post date:** [January 15, 2018, 10:51pm UTC](https://boards.straightdope.com/t/you-have-to-do-a-45-minute-presentation-with-no-preparation-right-now/797521/128 "2018-01-15T22:51:29Z")
I could manage: How I went from deciding, in 2000, that I wanted to see a total eclipse in my lifetime, to seeing one in 2017. Amateur musical theatre as a hobby: the highs and lows Jack White My experience as a volunteer at a wildlife sanctuary in Malawi Bereavement in its various forms, and how it really does get easier ---
**Author:** ![Wolf333](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/wolf333/32/3460_2.png) [@Wolf333](https://boards.straightdope.com/u/Wolf333)\ **Post date:** [January 15, 2018, 11:25pm UTC](https://boards.straightdope.com/t/you-have-to-do-a-45-minute-presentation-with-no-preparation-right-now/797521/129 "2018-01-15T23:25:57Z")
1. Why Recovering From Brain Surgery Is Worse Than Having Brain Surgery 2. The 7 Times I Experienced Anaphylaxis (Without Allergies) ---
**Author:** ![jonpluc](https://avatars.discourse-cdn.com/v4/letter/j/fbc32d/32.png) [@jonpluc](https://boards.straightdope.com/u/jonpluc)\ **Post date:** [January 16, 2018, 3:52pm UTC](https://boards.straightdope.com/t/you-have-to-do-a-45-minute-presentation-with-no-preparation-right-now/797521/130 "2018-01-16T15:52:39Z")
> [@Chronos](#): > > I’m a substitute teacher. This is pretty much my life. > > Today, for instance, I was presenting on the cauldron scene in the Scottish play. On Tuesday, I was presenting on the properties of parabolas and quadratic equations. On Monday, it was about physical vs. chemical changes, pure substances, and the different kinds of mixtures. > > Now, if you let me pick the topic, I’d probably do an introduction to special relativity. It’s really not nearly as tough as most folks think. Your doing it all wrong. You pick PE class to sub so you can show up to work in sweat pants. ---
**Author:** ![jonpluc](https://avatars.discourse-cdn.com/v4/letter/j/fbc32d/32.png) [@jonpluc](https://boards.straightdope.com/u/jonpluc)\ **Post date:** [January 16, 2018, 3:55pm UTC](https://boards.straightdope.com/t/you-have-to-do-a-45-minute-presentation-with-no-preparation-right-now/797521/131 "2018-01-16T15:55:21Z")
Cost of Regulation. [Previous page](https://boards.straightdope.com/t/you-have-to-do-a-45-minute-presentation-with-no-preparation-right-now/797521.md?page=6)