Mathematical Expeditions 1

This is part of an expedition throught the history of word problems. It is adapted from the book Mathematical Expeditions by Frank J. Swetz.

This is a word problem from old India related to love and fractions. Do you dare solving it?

The third part of a necklace of pearls, broken in a lover's quarrel, fell to the ground; its fifth part rested on the couch; the sixth part was saved by the lady; and the tenth part was taken by her lover. Six pearls remained. How many pearls composed the necklace?

Explain the procces and the answer using comments. Write your name and course.

END DATE: FEB 22nd

HAPPY NEW YEAR!!

As you now we have just started a new year, the year 2015. I have a very simple question for you, write everything you now about this number (is it even or odd, prime or composite, if composite which are its factors and which are its divisors, do some calculations with it, ...).

Use comments to answer, writing your name.

Time Goal: january 16th

Eratosthenes

In this post you will see a presentation about Eratosthenes, and then you will have to answer a test.

Read everything slowly. If you don't understand a word you can look it up in the dictionary.

Let see what you can learn about Eratosthenes

Date limit: november 19th

If you want you can make some comments to this post.

Click on "Read more"

Secret box

There is a box with 20 red balls, 10 green balls and 5 black balls. How many balls do we have to extract at least to get four balls with the same colour?

CLUE: Think about the worst possible situation.

Use comments to answer, writing your name.

(Translated from: 100 problemas de ingenio by Capó, M.)

Constitución de 1812

Como sabréis hoy es el 200 aniversario de la aprobación de la primera constitución española, la constitución de las Cortes de Cádiz. ¿Sabias que en uno de sus artículos habla de las matemáticas?


Encuentra el articulo (incluido el número) e inclúyelo en los comentarios con tu nombre y curso.

The code

H+A+R+D+W+O+R+K = 98%

K+N+O+W+L+E+D+G+E = 96%

A+T+T+I+T+U+D+E = 100%

Can you find the code that has been used to find out these percentages?


Clue 1: Each letter has a value.
Clue 2: The order is important.
Clue 3: Do you know the alphabet?

Magic Squares

A magic square of order 3 is an arrangement of 3x3 = 3² = 9 numbers, usually distinct integers, in a square, such that the 3 numbers in all rows, all columns, and both diagonals sum to the same constant. A normal magic square of order 3 contains the integers from 1 to 9.

Normal magic squares exist for all orders greater than 3, although order 1 magic square consists of a single cell containing the number 1. It's impossible to construct a magic square of order 2.

Iron plate with an order 6 magic square
 in Arabic numbers from China,
dating to theYuan Dynasty (1206-1368).

The constant sum in every row, column and diagonal is called the magic constant or magic sum, M.

Magic squares have fascinated humanity throughout the ages, and have been around for over 4,120 years. 

A magic square on the
Sagrada Familia church façade

There are magic squares in a lot of cultures, for example Egypt and India. They are on stone or metal and used as talismans, because people believed that magic squares had powers like longevity and prevention of diseases.

Source: Wikipedia

Now it's your turn:

Place integers from -4 to 4 in a magic square of order 3. Which number is the magic constant? How do you make your magic square? You have to do it in your notebook and show it to your teacher next wednesday january 11th.

Hypatia

In this post you will see a presentation about Hypatia, and then you will have to answer a test.

Read everything slowly. If you don't understand some words, please raise your hand and ask your teacher.

Do you know any more scientific women? You may find some of them in the hall of the high school.

Let see what you can learn about Hypatia

Click on "Read more"

If you want you can make some comments to this post.