Guesstimation 2.0 reveals the simple and effective techniques needed to estimate virtually anything – quickly – and illustrates them using an eclectic array of problems. A stimulating follow-up to Guesstimation, this is the must-have book for anyone preparing for a job interview in technology or finance, where more and more leading businesses test applicants using estimation questions just like these.
The ability to guesstimate on your feet is an essential skill to have in today's world, whether you're trying to distinguish between a billion-dollar subsidy and a trillion-dollar stimulus, a megawatt wind turbine and a gigawatt nuclear plant, or parts-per-million and parts-per-billion contaminants. Lawrence Weinstein begins with a concise tutorial on how to solve these kinds of order of magnitude problems, and then invites readers to have a go themselves. Guesstimation 2.0 features dozens of problems along with helpful hints and easy-to-understand solutions. It also includes appendixes containing useful formulas and more.
Guesstimation 2.0 shows how to estimate everything from how closely you can orbit a neutron star without being pulled apart by gravity, to the fuel used to transport your food from the farm to the store, to the total length of all toilet paper used in the United States. It also enables readers to answer, once and for all, the most asked environmental question of our day: "paper or plastic?"
Acknowledgments xi
Preface xiii
1 How to Solve Problems 1
2 General Questions 11
2.1 Who unrolled the toilet paper? 13
2.2 Money height 17
2.3 Blotting out the Sun 19
2.4 Really extra-large popcorn 21
2.5 Building volume 25
2.6 Mass of money 29
2.7 A baseball in a glass of beer 33
2.8 Life on the phone 37
2.9 Money under the bridge 41
2.10 Monkeys and Shakespeare 45
2.11 The titans of siren 49
2.12 Airheads at the movies 53
2.13 Heavy cars and heavier people 55
2.14 Peeing in the pool 59
3 Recycling: What Really Matters? 63
3.1 Water bottles 67
3.2 99 bottles of beer on the wall . . . 71
3.3 Can the aluminum 75
3.4 Paper or plastic? 79
3.5 Paper doesn't grow on trees! 83
3.6 The rain in Spain . . . 87
3.7 Bottom feeders 91
3.8 You light up my life! 95
4 The Five Senses 101
4.1 Don't stare at the Sun 103
4.2 Men of vision 105
4.3 Light a single candle 109
4.4 Oh say can you see? 113
4.5 Bigger eyes 117
4.6 They're watching us! 121
4.7 Beam the energy down, Scotty! 125
4.8 Oh say can you hear? 131
4.9 Heavy loads 135
5 Energy and Work 139
5.1 Power up the stairs 143
5.2 Power workout 145
5.3 Water over the dam 149
5.4 A hard nut to crack 153
5.5 Mousetrap cars 155
5.6 Push hard 159
5.7 Pumping car tires 161
5.8 Pumping bike tires 165
5.9 Atomic bombs and confetti 169
6 Energy and Transportation 173
6.1 Gas-powered humans 177
6.2 Driving across country 181
6.3 Keep on trucking 185
6.4 Keep on biking 189
6.5 Keep on training 193
6.6 Keep on flying 197
6.7 To pee or not to pee 201
6.8 Solar-powered cars 205
6.9 Put a doughnut in your tank 209
6.10 Perk up your car 213
6.11 Don't slow down 217
6.12 Throwing tomatoes 219
7 Heavenly Bodies 223
7.1 Orbiting the Sun 227
7.2 Flying off the Earth 229
7.3 The rings of Earth 233
7.4 It is not in the stars to hold our destiny 237
7.5 Orbiting a neutron star 241
7.6 How high can we jump? 245
7.7 Collapsing Sun 249
7.8 Splitting the Moon 253
7.9 Splitting a smaller moon 257
7.10 Spinning faster and slower 263
7.11 Shrinking Sun 267
7.12 Spinning Earth 271
7.13 The dinosaur killer and the day 273
7.14 The Yellowstone volcano and the day 277
7.15 The orbiting Moon 281
7.16 The shortest day 283
8 Materials 289
8.1 Stronger than spider silk 291
8.2 Beanstalk to orbit 295
8.3 Bolt failure 299
8.4 Making mountains out of molecules 303
8.5 Chopping down a tree 307
9 Radiation 311
9.1 Nuclear neutrinos 315
9.2 Neutrinos and you 319
9.3 Solar neutrinos 323
9.4 Supernovas can be dangerous 327
9.5 Reviving ancient bacteria 331
9.6 Decaying protons 335
9.7 Journey to the center of the galaxy 337
Appendix A
Dealing with Large Numbers 341
A.1 Large Numbers 341
A.2 Precision, Lots of Digits, and Lying 343
A.3 Numbers and Units 345
Appendix B
Pegs to Hang Things On 347
Bibliography 351
Index 355
Lawrence Weinstein is University Professor of Physics at Old Dominion University. He is the coauthor of Guesstimation: Solving the World's Problems on the Back of a Cocktail Napkin.
Patricia Edwards is senior lecturer in art at Old Dominion University. A graduate of the Rhode Island School of Design, she lives in Norfolk, Virginia.
"This follow-up to the popular Guesstimation offers more on the joy of mathematical estimation, and inspiration for the budding analyst."
– Nature
"The books do a wonderful job at helping the reader to master the craft."
– Cut the Knot Insights
"A delightful volume [...] I hope to be able to use many of the tricks I learned in the future. I also hope to teach some of them to students. This would make a great secondary textbook in many classes, ranging from quantitative literacy to a science methods class for future educators. A careful study of this book would certainly improve a student's ability to take a complicated question, break it down into solvable parts, and assemble the parts to find an answer. Because this is quite close to what I want my students to do when faced with a difficult problem in pure mathematics as well, I consider this to be a very valuable book indeed."
– Dominic Klyve, MAA Reviews
"Guesstimation 2.0: Solving Today's Problems on the Back of a Napkin succeeds where most popular science literature so often fails. This is because it provides its readers with a scientific tool they can use immediately in their everyday lives [...] [Makes] an excellent addition for the casual scientist, job interviewee, or anyone hoping to impress their friends at a party."
– Gabriel Thoumi, Mongabay.com
"This is an absolutely great book, a worthy sequel to Guesstimation. The breadth of scope of the problems is truly impressive. Weinstein's arguments are always convincing and, in many cases, very clever. His sense of humor provides a pain-free tutorial on how analysts can make real progress in understanding vaguely defined problems."
– Paul J. Nahin, author of Number-Crunching: Taming Unruly Computational Problems from Mathematical Physics to Science Fiction
"Guesstimation 2.0 is an entertaining read, with the added attraction that it can be consumed in small portions by opening it on almost any page. I can easily see having this book close by and returning to it again and again."
– Mark Levi, author of Why Cats Land on Their Feet: And 76 Other Physical Paradoxes and Puzzles