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Fraction comparison for 4th Graders.

They’ve been working a lot with representing fractions as circles and as rectangles. They’ve done some basic addition with fractions. Most aren’t generally able to find equivalent fractions. What mistakes do you expect to see in the class set? Make a prediction! In the comments, would you please answer this question: Which mistake most surprised you? Kid 1 Kid 2 Kid 3 Kid 4 Kid 5. We used this image today to create our own proportion problems.

Shown here is how much data is generated at each company after 1 minute. I took the screen shot from this site Here was my example of a proportion problem: “If there are 48818 apps downloaded in a minute from Apple, how many in one day?” My students then designed their own problems to solve……..we then wrote them on the board and everyone picked some to solve….here are a couple: My kids were engaged and wanted to solve each others problems ……just to see how crazy the data was. Like this: Like Loading... Related Let's Start with the Easy Ones Here's how I taught students how to solve trigonometric equations in our grade 12 advanced functions class. November 27, 2014 In "3act Math" Stacking Cups! So we did Dan's Meyer's stacking cups lesson in class today!!!

November 12, 2014 In "Class Activities" Popcorn Pandemonium. Colonnes. Chômage : l’inversion de la courbe, c’est pour 2016. Pas de chance !

Chômage : l’inversion de la courbe, c’est pour 2016

Le nombre de chômeurs complets, ou de catégorie A, qui avait baissé de 19.000 en janvier, remonte de 12.000 en février. Le « bilan » global des deux premiers mois de 2015 est ainsi de - 7.000, mais le chiffre est quand même mis au passif du gouvernement. Dès jeudi soir, Manuel Vals était obligé de « monter au créneau » et Nicolas Sarkozy agressait François Hollande sur ce point lors d’une réunion électorale dans le Nord. Exagérément, et vulgairement d’ailleurs et bien dans sa faconde, car François Hollande n’a pas réitéré l’erreur de promettre une « inversion de la courbe » à une date donnée. Il faut dire que la prévision du président début 2013 d’un retournement en fin d’année, non seulement ne s’est pas réalisée, mais ne l’a même pas été en 2014 ! Jean Matouk Un second graphique montre comment évoluent ensemble le taux de croissance du PIB en volume, c’est-à-dire sans hausse des prix- et l’emploi salarié.

Before the iPhone, man had rocks.

The first true multi-tools were of course rocks. Take the chopper, a crude tool chipped from the volcanic stone nephelinite. First used in Tanzania some 1.85 million years ago, it was the stone-age equivalent of the smartphone. Grant me the imperfect comparison: For thousands of years, the chopper served most of humanity’s needs. As Earth spins on its axis every 24 hours, one side of the planet is illuminated by light from the Sun.

This gives one-half of the planet its day, and at the same time the other half is immersed in night. While the Earth does not naturally emit any visible light, technology from humans has certainly made our planet brighter when facing away from the Sun. This image is a composite of two sets of data— one of the globe reflecting sunlight and another of the globe in full darkness, showing only the bright lights of inhabited areas. Download high-res image file | Download caption as .zip file Globo Terrestre Asia Al girar la Tierra sobre su eje cada 24 horas, un lado del planeta está iluminado por la luz del Sol. Download high-res image file | Download caption as .zip file. Small Cubicuboctahedron – Robert Webb This is the small cubicuboctahedron, as drawn by Robert Webb’s Great Stella software.

It looks simple enough, but it conceals some interesting mathematics. For starters, the yellow pieces are actually regular octagons which are mostly hidden from view. The three shades of yellow are parts of three octagons, but there are also three more, each parallel to a plane containing a red square. Thus, this polytope has 3 kinds of faces: • 6 red squares, • 8 blue equilateral triangles, and • 6 yellow octagons. Don’t be fooled by how the octagons cross each other. As you trace out a small loop traversing all the faces that meet at a vertex, crossing edges and ignoring false edges, you traverse first a square, then an octagon, a triangle, then another octagon… and finally you return to where you started. So, this polytope has regular polygons as faces, and every corner looks like every other: more precisely, its symmetry group acts transitively on the vertices.