PLACE VALUE
In the number 3 147 286 (three million, one hundred and forty seven thousand, two hundred and eighty six), the figure 2 has a value of 200 (two hundred), and the figure 3 has a value of 3 000 000 (three million).
Exercise 1.–
What is the value of the position 3 in the number 385939584? What is the value of the position 6?
e) Describe the numbers 4.235 225 in words.
Use < (less than), equals (=) or > ( greater than) to compare each set of numbers.
Tests of divisibility
Exercise 3.–
Hot Potatoes about divisibility. Ask for it at my mail: migueles0709@hotmail.com
Introduction
Exercise 2.–
a) Describe the number 79 in words.
b) Describe the number 348 in words.
c) Describe the numbers 9 139 in words.
d) Describe the numbers 125 .978 in words.
e) Describe the numbers 4.
COMPARING NUMBER
Symbol | Meaning | Example in symbols | Example in words |
> | Greater than | 9 > 3 | 9 is greater than 3 |
< | Less than | 3 < 9 | 3 is less than 9 |
= | Equal to | 9 = 9 | 9 is equal to 9 |
Exercise 1.–
Use < (less than), equals (=) or > ( greater than) to compare each set of numbers.
a.) 19 and 15.
b.) (24 – 18) and 6.
c.) 23 and (100 – 77)
DIVISIBILITY
Tests of divisibility
Here are some quick and easy checks to see if one number will divide exactly.
Divisible by 2.
A number is divisible by 2 if the last digit is 0, 2, 4, 6 or 8.
Example: 2346 is divisible by 2 since the last digit is 6.
Divisible by 3.
A number is divisible by 3 if the sum of the digits is divisible by 3.
Example: 23457 is divisible by 3 since the sum of the digits is 21 (2 + 3 + 4 + 5+ 7 = 21), and 21 is divisible by 3.
Divisible by 4.
A number is divisible by 4 if the number formed by the last two digits is either 00 or divisible by 4.
Example: 245678952152 is divisible by 4 since 52 is divisible by 4.
Divisible by 5.
A number is divisible by 5 if the last digit is either 0 or 5.
Example: 12457896535 is divisible by 5 since the last digit is 5.
Divisible by 6.
A number is divisible by 6 if it is divisible by 2 and it is divisible by 3.
Example: 256848 is divisible by 6 since it is divisible by 2 and 3.
Divisible by 11.
To check whether a number is divisible by 11, sum the digits in the odd positions counting from the left (the first, third, ....) and then sum the remaining digits. If the difference between the two sums is either 0 or divisible by 11, then so is the original number.
Example: 145879635
Digits in the odd positions: 1+5+7+6+5 = 24
Digits in the even position: 4+8+9+3 = 24
So 145879635 is divisible by 11 since 24-24=0.
Exercise 1.–
Try to write the test of divisibility by 10.
Exercise 2.–
Using the tests of divisibility, complete the following table:
| Divisible by | 2 | 3 | 4 | 5 | 6 | 10 | 11 |
| 28457 | | | | | | | |
| 1211100 | | | | | | | |
| 17160 | | | | | | | |
Exercise 3.–
Hot Potatoes about divisibility. Ask for it at my mail: migueles0709@hotmail.com
Treasure Hunt about Egyptian numbers
We are going to work on the topic of "The Egyptian numbers". Sure that you have heard speaking about the pyramids, the hieroglyphs and probably you have seen some movie which happens into the former Egypt, but do you know how they were counting? Did they realize operations?
In this work you will learn in a way simple how the Egyptians calculated. For it, we are going to use a series of web pages that I have selected, in this way you will not lose too much time in looking for these information.
I HOPE THAT YOU ENJOY!
Task
Along this work you go to elaborate a document with the title "The Egyptian numbers" in that you will develop the following paragraphs:
1. Title.
2. Introduction: what is going to explain...
3. Documents that refer to Egyptian Mathematics.
4. Egyptian systems of numeration: symbols used in each of them...
5. Egyptian measures.
For all this, you will be able to help with drawings, images, texts... that exist in the web pages proposed in the paragraph of "resources".
This work will be presented in electronic format.
Process
To realize this task you will form groups of three persons and you will have to distribute the work.
You have to consult the web pages proposed in the paragraph of resources and selecting the information. In the work that you will deliver the paragraphs will have to appear as minimum mentioned previously.
Resources
The following web pages will be used:
Evaluation
The work is going to be valued on 100 points, distributed like it indicates the following table:
Category | Valuation |
Title | 5 |
Introduction: what is going to explain... | 15 |
Documents that refer to Egyptian Mathematics | 20 |
Egyptian systems of numeration: symbols used in each of them... | 20 |
Egyptian measures | 15 |
Applications | 15 |
Draft | 10 |
Conclusion.
I hope that this work has served you to know since the mathematics arise in one of the ancient civilizations.
