This is our final Math Monday blog. This is the last time I will be writing about math. I am so happy for school to end. Did you know that next year we will be writing about math in our math classrooms. It will be very similar to the way I am writing this blog. Our math standards are changing The entire U.S.A's math standards are changing except for two states. These two states are sticking with their own standards for education. The downside of sticking with their own standards is that their standards aren't going to similar to the other states. There are problems when students transfer states. Since standards are different, their are problems. When students from California transfer to states like New York, their is a lot of trouble since their standards are different.
To determine how much hair is on someone's head, you must first determine the area of the head by using the mathematical equation used to determine the area of a circle. In this case the circle will be the head. After determining the area of you head, you must determine how much hair fits in a specific amount of area. I will use some examples to demonstrate. The area of my head is 20 inches^2. In 4 inches^2 There is 100 hair. Therefore, the total amount of hair is 500 because you would multiply 100 by 5. The step I just showed needs some further explaining. We are using proportions right now. If you put 20 inches over 4 inches, that simplifies down to 5. You would then multiply 5 by the 100 because 4 out 20 inches is 1/5, and you need to know the whole. Therefore, you will multiply by the reciprocal which is 5. 100*5=500.
Math is used in most parts of science. Probability is used in genetics to determine what type of genes a newborn is likely to have. Algebra and geometry are used in physics. One example would be e=mc^2. This equation shows energy. It uses variables which are e, m, and c. It also has exponents. NASA uses lots of math to determine when to launch rockets, how long the rocket should be, how long should the fins be. How wide should the fins be. Science uses a lot of math. Calculus can be used to determine the perimeter of a curved object.
Conversion is also used. 1 inch=2.54 centimeters. Did you know that the last rocket launch to mars failed because someone forgot to convert inches to centimeters, and the parachute deployed to late. Math is everywhere. I will use a parabola as an example. A parabola can be used to show a rocket and how long it takes until it will hit the ground after launch off. These are all examples of how math is used in science. Negative Numbers can be used to show debt. Debt is when you owe someone money. If you owe someone $30. Then you are -30. If you have $30, then you are +30. Do you see the difference? I hope so. Here is another example, if someone has $30 of Starbucks credit and they buy a venti frappucino for $5. It will show -$25 on the screen. If you did not have any store credit, then it would $5. Do you see the difference? It shows -$25 dollars because the company owes you money. The $25 dollars are being shown from the company's point of view. Here is another example. If you put money in your bank account it is +. If money is deducted, then it is -.
Another example of negative numbers would be in stocks. Here is an example. Homer Simpson invest $1000 in stock. If the company he invested in makes profit, then he will get more money. If the company he invested loses money then Homer Simpson will get less than $1000. This is another example of negative numbers. On January 1st it is 59 degrees Fahrenheit. On January 2nd it is 32 degrees Fahrenheit. The change in temperature is 27. These are a few examples which show how negative numbers are used in real life. The equation 2x-7=15 is like a balance equation. The only difference is that there are 0x's on the right side of an equation, but if it helps; I will put 0x. 2x-7=0x+15. What are you left with if you subtract 0x from both sides? You are left with 2x-7=15. Since the x's were eliminated on the right side, we have to eliminate the units on the left side. Therefore, we must add 7 to both sides. Leaving us with 2x=22. Since we need to know what one x is and not two x, we must divide both sides by 2 leaving us with x=11. =
Now let me further explain. The goal is to figure out what 1x equals. There is no benefit of knowing that 2x-7=15. You MUST attempt to figure out what x is all by itself. There is only one way to get rid of -7, and that is by adding +7. After you do that, you are left with 2x=22. Since x is just a variable, let's think of x as a different variable. Let's use the variable Δ (delta). 2Δ=22. We need to know what Δ is not 2Δ. Therefore we will divide both sides of the equation by 2. This leaves us with Δ=11. I think that the most exciting math lesson this year would be quadratic functions and quadratic equations. It seems interesting how you can know how high or how fast, an object is going, and get an accurate prediction when it will reach the vertex, the maximum or the minimum. I feel very nervous about the CSTs. They are coming up very soon, and on the previous ACS, there were somethings I didn't know such as parabolas and quadratic functions. Thank God we're not being tested on radicals. Mr. Erickson said that he was going to teach us radicals after the CSTs since we weren't tested on them. I still want to learn radicals anyway. Just in case they do show up on the CST. Quadratic functions are everywhere. If you see an arch, there will be a mathematical equation. You will see an arch below, and there is a quadratic equation for it if someone ever wanted to know it. The arch below is an example of how quadratics are used in real life.  The best way to do show you my methods of conversion is through showing them to you. Let's use .54 as an example. The first thing is to move the decimal over 2 places to the right and put it over 100. This gives you 54/100. The next step is to divide both the numerator and the denominator by the same number. I will divide by 2. This leaves us with 27/50. This can not be simplified. We are now done. I will show you another example.
This time I will use 80/100. I will divide the numerator and denominator by a common number. Since both the numerator and the denominator are divisible by 10, I will divide 80/100 by 10. This leaves us with 40/50. Since both the numerator and the denominator are divisible by 10, I will divide them by ten leaving use with 4/5. Instead of dividing twice, I could have divided 80/100 by 20 which would have left use with 4/5. In my opinion, this is the best method to converting decimals to fractions, and this is the only method I know. If there is a different method please post this method in the comments, and also if you like this method more than the method you were taught; please let me know in the comments. The first method is Renaming. It is when you multiply the fraction until it begins with 1, and is a multiple of 10. Such as 10, 100, 1000, 10000, and etc. I do not prefer this method. I prefer the division method. It is when you divide the numerator by the denominator. I will now demonstrate both methods. The first method, I will use 4/25. I will multiply it by 4 which gives me 16/100. This method may seem really good, but what will you do when you get a number like 4/7.
You would have to multiply 4/7 by a number like 14.2857142857. Numbers like these are really ugly. Now, I will demonstrate the second method using 4/25. 4 divided by 25 is 0.16. This method is easy to use with numbers like 4/7 as well. 4 divided by 7 is 0.57142857142. This number is long, You would have gotten the same answer through both methods. It is a matter of how you get there. The second method is a lot faster and efficient. I personally prefer this method since this method is a lot easier. I would personally use a ratio. An example of a ratio would be 5 cherry red lollipops : 2 green apple lollipops. This means that your cherry red lollipops sell 2.5 times as much as a green apple lollipops. The percent would be 250% cherry red lollipops. How do you get 2 1/2 lollipops? You don't that is why you would use a ratio. If you say 500 percent than it would be 5 lollipops to 1 lollipop. This is why ratios work better than percents.
In my opinion, percents are best things with discounts such 25% of a $100 jacket. A ratio would be 75:100, and therefore in this situation, a percent would be better. But since the blog topic is on which is better to use when buying food, I would have to say ratios. To determine the area, you need to know the radius. In this case, the radius is 3 feet. To find the area, you use the equation area=Pi*radius^2. Since the radius is 3 feet, when you square it, you get 9 feet squared. The next step is to multiply 9 feet squared with Pi, you get 9Pi which is the area. To determine the circumference, you need to know the diameter or the radius. If you know the radius, double it to get the diameter. The equation to determine the circumference is circumference=diameter*Pi. Since the radius is 3 feet, the diameter is 6 feet. If you multiply the diameter with Pi, you get 6Pi. This is how you determine the area and circumference of a circle.
Pi is found everywhere nature. When Pi was first discovered by ancient mathematicians, they were very fascinated. Pi has an infinite number of digits. There is no final digit for pi, and there is no pattern that has been discovered yet. | AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesJune 2013 Categories |
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