Approximations | Informal estimation

Back-of-the-envelope calculation

A back-of-the-envelope calculation is a rough calculation, typically jotted down on any available scrap of paper such as an envelope. It is more than a guess but less than an accurate calculation or mathematical proof. The defining characteristic of back-of-the-envelope calculations is the use of simplified assumptions. A similar phrase in the U.S. is "back of a napkin", also used in the business world to describe sketching out a quick, rough idea of a business or product. In British English, a similar idiom is "back of a fag packet". (Wikipedia).

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Use the midpoint formula to find the endpoint when given the midpoint ex 2

👉 In this playlist, you will learn what the distance and midpoint formulas are and how to apply them. The distance formula is derived from the Pythagorean theorem given the coordinates of two points. We will use the distance and midpoint formula to not only determine the distance and mid

From playlist Find the End Point of the Line Segment

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Statistics - Compute the interquartile range

This video shows how to compute the interquartile range for a set of data. Remember to reorganize the data so that you can find the median values easier. For more videos visit http://mysecretmathtutor.com

From playlist Statistics

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Find the endpoint when given midpoint and other endpoint ex 1

👉 In this playlist, you will learn what the distance and midpoint formulas are and how to apply them. The distance formula is derived from the Pythagorean theorem given the coordinates of two points. We will use the distance and midpoint formula to not only determine the distance and mid

From playlist Find the End Point of the Line Segment

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Example: Determine the Distance Between Two Points

This video shows an example of determining the length of a segment on the coordinate plane by using the distance formula. Complete Video List: http://www.mathispower4u.yolasite.com or http://www.mathispower4u.wordpress.com

From playlist Using the Distance Formula / Midpoint Formula

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Find the endpoint given one endpoint and midpoint Mistake

👉 In this playlist, you will learn what the distance and midpoint formulas are and how to apply them. The distance formula is derived from the Pythagorean theorem given the coordinates of two points. We will use the distance and midpoint formula to not only determine the distance and mid

From playlist Find the End Point of the Line Segment

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Determine the endpoint given one endpoint and midpoint algebraically

👉 In this playlist, you will learn what the distance and midpoint formulas are and how to apply them. The distance formula is derived from the Pythagorean theorem given the coordinates of two points. We will use the distance and midpoint formula to not only determine the distance and mid

From playlist Find the End Point of the Line Segment

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How to determine the endpoint, given one endpoint and midpoint

👉 In this playlist, you will learn what the distance and midpoint formulas are and how to apply them. The distance formula is derived from the Pythagorean theorem given the coordinates of two points. We will use the distance and midpoint formula to not only determine the distance and mid

From playlist Find the End Point of the Line Segment

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The Distance Formula

This video show how to use the distance formula to determine the distance between two points. It also shows how it is derived from the Pythagorean theorem. http://mathispower4u.yolasite.com/

From playlist Using the Distance Formula / Midpoint Formula

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13. Dispersive Medium, Phase Velocity, Group Velocity

MIT 8.03SC Physics III: Vibrations and Waves, Fall 2016 View the complete course: https://ocw.mit.edu/8-03SCF16 Instructor: Yen-Jie Lee Sending a square pulse as a basic communication tool is the main focus of this lecture. Prof. Lee discusses the phenomenon of dispersion in a realistic m

From playlist MIT 8.03SC Physics III: Vibrations and Waves, Fall 2016

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Lecture 18: Weight and Balance

MIT 16.687 Private Pilot Ground School, IAP 2019 Instructor: Philip Greenspun, Tina Srivastava View the complete course: https://ocw.mit.edu/16-687IAP19 YouTube Playlist: https://www.youtube.com/playlist?list=PLUl4u3cNGP63cUdAG3v311Vl72ozOiK25 This lecture discussed the topic of weight an

From playlist MIT 16.687 Private Pilot Ground School, IAP 2019

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Shock waves and gamma-ray bursts from neutron star mergers - Andrei Beloborodov

Institute for Advanced Study Astrophysics Seminar Topic: Shock waves and gamma-ray bursts from neutron star mergers Speaker: Andrei Beloborodov Affiliation: Columbia University Date: October 8, 2020 For more video please visit http://video.ias.edu

From playlist Astrophysics Seminar

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The Surprisingly Dynamic...Massive Stars - Eliot Quataert

Joint IAS/Princeton University Astrophysics Colloquium Tuesday, October 27, 2015 http://www.sns.ias.edu/~seminar/colloquia.shtml In the last few years of the lives of massive stars, fusion in the core of the star produces a nuclear power that greatly exceeds the Eddington luminosity. Thi

From playlist Joint IAS/PU Astrophysics Colloquium

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How to Do Maths Without a Calculator - with Rob Eastaway

Knowing how to quickly estimate sizes and numbers is a useful everyday application of maths. Buy Rob's book "Maths on the Back of an Envelope" now - https://geni.us/yaeUJw How many cats are there in the world? What's the chance of winning the lottery twice? And just how long does it take

From playlist Mathematics

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That weird light at the bottom of a mug — ENVELOPES

Envelopes are cool. Interactive Demos on Desmos: https://www.desmos.com/calculator/ihms56f994 https://www.desmos.com/calculator/thozshn9l5 Did I get anything wrong? Let me know! I swept over a lot of interesting things here to keep it short! This was made as part of 3Blue1Brown's Summe

From playlist Summer of Math Exposition Youtube Videos

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Arthur Ogus - Prisms, prismatic neighborhoods, and p-de Rham cohomology

Correction: The affiliation of Lei Fu is Tsinghua University. Prismatic cohomology, as proposed by B. Bhatt and P. Scholze, provides a uniform framework for many of the cohomoogy theories involved in p-adic Hodge theory. I will focus on the crystalline incarnation of prismatic cohomology

From playlist Conférence « Géométrie arithmétique en l’honneur de Luc Illusie » - 5 mai 2021

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How to calculate margin of error and standard deviation

In this tutorial I show the relationship standard deviation and margin of error. I calculate margin of error and confidence intervals with different standard deviations. Playlist on Confidence Intervals http://www.youtube.com/course?list=EC36B51DB57E3A3E8E Like us on: http://www.facebook

From playlist Confidence Intervals

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Richard Rimanyi - Stable Envelopes, Bow Varieties, 3d Mirror Symmetry

There are many bridges connecting geometry with representation theory. A key notion in one of these connections, defined by Maulik-Okounkov, Okounkov, Aganagic-Okounkov, is the "stable envelope (class)". The stable envelope fits into the story of characteristic classes of singularities as

From playlist 2021 IHES Summer School - Enumerative Geometry, Physics and Representation Theory

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Code-It-Yourself! Sound Synthesizer #2 - Oscillators & Envelopes

This second video improves upon the basic waveform generators in the last video, to produce a flexible oscillator. The amplitude of the oscillator is now controlled by an Attack, Decay, Sustain, Release envelope, to produce some more realistic instrument sounds. All the code is available

From playlist Code-It-Yourself!

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Lecture 16 (CEM) -- Beam Propagation Method

This lecture steps the student through the formulation and implementation of a basic finite-difference beam propagation method. A brief overview of wide-angle and bi-directional BPM is given, but not discussed in detail. Prerequisite Lectures: 10

From playlist UT El Paso: CEM Lectures | CosmoLearning.org Electrical Engineering

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Finding one endpoint when given a midpoint and endpoint

👉 In this playlist, you will learn what the distance and midpoint formulas are and how to apply them. The distance formula is derived from the Pythagorean theorem given the coordinates of two points. We will use the distance and midpoint formula to not only determine the distance and mid

From playlist Find the End Point of the Line Segment

Related pages

Guesstimate | Order of magnitude | Mathematical proof | Fermi problem | Calculation