Decimal Numbers By: Jennifer Paola Caro and Juanita Suarez 4A
Objectives • To learn which is the importance of decimal numbers in daily life. • To learn how to use decimal numbers and to know the different ways to represent and to use decimal numbers. • To understand how are fraction, moneys, pictures and unit related with decimal numbers
¿What are decimal numbers ? They are the numbers that come when we divide an unit that we can count based on the number ten. Decimals most of the time work with fractions by using the drawing to divide the unit. Decimals only base on the number ten so we only have to put one zero.
¿Where can I find decimal numbers? We also can find decimal numbers in the cents and the dollars because its value is write as a decimal number so we add the prices to get a bigger decimal number that is the total.
¿How can we represent decimal numbers? We can represent it with the pictures and the fractions. We can represent it mix in the place value and the word name We can represent it by the money , the dollars and the cents.
Parts of the decimal number This number show the entire unit, if the unit is complete is going to appear other number and if the unit is not complete we have to put a zero. This numbers expresses the value of the the incomplete unit when it is divide . It divides the two different parts from each other.
¿How are the fractions and the decimals similar? • They are similar because when the unit is divide we can write that as a fraction using the divide parts that are color and also we can count the parts of the unit and write them as a decimal number.
How to add decimal numbers • First, write a number below the other but in the way that the first and the last number are aligned, remember that the number 11 that is before the point we don´t have to put that 1 below that number 2 because they are two different parts like this: Then, star adding each column and remember to start by the right side like this
How to add decimal numbers with money First, add the cents but start adding the ones in the cents like 0.25 add only the 5 with the other ones in the case that the total pass from 9 put the complete numbers in this example it is 22. Then, add the tenths of the cents like this 0.50 add the 5 with the other tenths in this case you don´t have space to put the total that is 10 so add the first numbers that is 1 to the dollars Finally, add the dollar the total is 16 but because the one that you add of the tenths the total is $17.22
Pictures and decimals • This two numbers are decimal numbers: 0.1 0.01 But are they the same? No When the number has only one zero it is base on the 10 and in the pictures we have to color only one line like this : When the number has two zeros it is base on the 100 so in the picture we only have to color one square like this: In some problem solving the 0.01 will appear like 0.1 and 0.1 will appear like only the 1.
Examples • Decimal numbers with fractions and units. • Decimal numbers with money
Problem solving Pizza Hamburger If you buy a pizza and a hamburger, how much do you have to pay? We have to pay $9.48
Problem solving • Karla got in her exam 79.09, Carlos got 79.1 and Paola got 79.02 in her exam, who got the best grade? Who got the worst grade? • To solve this problem I´m going to make a list from least to greater. 79.02 79.09 79.1 1 1 Carlos gets the best grade and Paola gets the worst grade 2 3
Problem solving • To make a miniature ice cream truck, you need tires with a diameter between 1.465 cm and 1.472 cm. Will a tire that is 1.4691 cm in diameter work? Explain why or why not. We must compare and order this decimals to help us solve this problem. We have to make a list from least to greater. 1.4650 1.4691 1.4720 1 2 3 Yes it work because 1.472 is the greater cause it has seven not a six so 1.4691 is between the two other numbers When we are going to make an operation or list and one decimal has more numbers we have to put to the other a zero until all the numbers are aligned
How can help us decimal numbers in daily life Decimal numbers can help us a lot with the issue of money because now the dollars and cents are used in most of the world also help us a lot in that part of the engineering that is to measure things and to now in decimal numbers how much measure each side or to know how much equal parts or liters of cement is needed and to add the decimal to get a total but as well, decimal numbers are used for many things.
Conclusions As well, we understand that decimal numbers are used for many things also, that this is a knew topic that you can learn if you put attention and that is not so difficult to understand. THE END