How Many? The Art of Guesstimation
Learn to estimate almost anything—from the number of piano tuners in Chicago to the golf balls that fit in a bus—using simple logic and the back-of-the-envelope method.
Like Duolingo, but for How Many? The Art of Guesstimation. Tomo turns the whole topic into a game you play five minutes a day, until it actually sticks.
A short one: 9 levels across 2 sections, about 18 minutes end to end, roughly 4 days at five minutes a day. It moves through The Power of the Guesstimate and Refining Your Logic. It starts from scratch.
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Key ideas in How Many? The Art of Guesstimation
- Estimates identify if an idea is worth pursuing or a total non-starter
- Visualizing a small, manageable 'box' or section first
- A rough count is enough to change a 'yes/no' decision even without precision
- Counting the individuals inside that single section
- The goal is to avoid big mistakes, not to predict the exact profit
- Multiplying that count by the total number of sections in the area
- The purpose of a back-of-the-envelope calculation in decision making
- The steps of the Box Method for area estimation
- Rounding to numbers with zeros makes multiplication possible in your head
- Small rounding errors usually cancel each other out in a large estimate
- Speed in estimation is more valuable than tracking every digit
- A range accounts for the uncertainty of a guess
- Rounding to the nearest power of ten for mental math
- Incomplete data is the normal starting point for most real-world problems
- A 'good enough' guess is better than no information at all
- Using a range to increase confidence in an estimate
You've tried the other tabs
Thirty open tabs. Four facts you actually kept.
You watched. You nodded. By Sunday it was gone.
One answer, then back to scrolling.
Eight weeks. You meant to finish. You didn't.
Tomo gives How Many? The Art of Guesstimation the Duolingo treatment: levels, streaks, and quick quizzes that test what you just learned. That game loop is what the tabs above never had, so it's the one you actually finish.
Here's what playing it feels like
A real question from this course. Take your best guess.
When using the Box Method to count a huge crowd, what is your very first move?
Get it right to open this lesson and 8 more in the app.
How to learn How Many? The Art of Guesstimation, step by step
Go in order. 9 short levels across 2 sections, about 18 minutes in all, five minutes a day.
- 1
The Power of the Guesstimate
- Your First Back-of-the-Envelope Calculation
- Breaking Big Questions into Small Pieces
- 2
Refining Your Logic
- Thinking in Orders of Magnitude
2 sections · 3 units · 9 levels. Built to play, not to enroll.
Questions about How Many? The Art of Guesstimation
How do I learn How Many? The Art of Guesstimation?
Go in order: start with The Power of the Guesstimate, then Refining Your Logic. On Tomo that's 9 short levels, about 18 minutes in all, played five minutes a day. Start free and play the first level in under a minute.
Is there a Duolingo-style app for How Many? The Art of Guesstimation?
Yes. Tomo works like Duolingo: short daily lessons, streaks and quick quizzes. How Many? The Art of Guesstimation is one of its free courses, and you can type any other topic to get a course of your own.
Is the How Many? The Art of Guesstimation course free?
Yes. How Many? The Art of Guesstimation is playable on Tomo's free plan, which doesn't expire. No credit card, no waitlist. Download the app and start your first lesson.
How long does it take to learn How Many? The Art of Guesstimation?
9 levels across 2 sections, about 18 minutes of play in total. It's built for five minutes a day, so you finish it a little at a time instead of all at once.
Do I need any background to start How Many? The Art of Guesstimation?
No. It's pitched at a beginner level, so it starts where you are and builds up. If you can tap a phone, you can start.
Tomo is in ChatGPT
Tomo is also a ChatGPT plugin: the same playable courses, built and played inside your chat.
Add Tomo to ChatGPT- What to ask
- “Make me a Tomo course on black holes.” “Turn this chat into a Tomo course.”
- What you get
- Quick questions with instant feedback, hearts and stars, ready to play in about a minute.
- Where it goes
- No sign-up to start. Connect your Tomo account and your streak carries on in the app.
You pick the voice
How Many? The Art of Guesstimation is taught in the Bestie style: your friend who just gets it. Want a different feel? In the app you can spin up the same topic in any of Tomo's teaching styles. Same facts, totally different vibe.
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Start How Many? The Art of Guesstimation today.
Download Tomo, search How Many? The Art of Guesstimation, and play your first lesson in under a minute.