Math- What I learned about grade 9 fracrions

Fractions on number lines and comparing

During this unit, we ran into fractions (negatives and positives) and we got a lot of hints on how to know which number is bigger or smaller, although sometimes it’s just common sense however not always. A number line is a visual to help you see which of the two is the larger number. When a number goes into the negatives (left side of zero ) you know that it will be smaller than the number on the positive side (right side from zero). The easiest way to compare numbers, in my opinion, is by using a number line. When your comparing numbers and wanting to place them on a number line, you just look at the bottom number (aka. the denominator) to see the number of jumps before you make it to a full number. On the other hand, the number on the top (aka. numerator) shows how many jumps you have already done. Number lines are a great visuelle !

Adding/subtracting fractions

When you are adding or subtracting two (or multiple) fractions you have to find their common denominator. Supposing you have a negative fraction can change the whole outcome of the equation. Let’s say that you have and you want to add   you would have to find a common denominator and their common denominator is 8, although you multiply the denominator by 2 you would also have to do have to multiply the numerator as well and that would mean ur fractions would be plus . Once you have got that done you can know add the two, which means your outcome is . If you don’t have the  negative sign there your outcome would have been positive . A negative + positive = thug a war, negative + negative = negative, positive + positive = positive.

When you are substracting a positive it is pretty much the same ass just adding the two numbers together, however you still need to find a commun denominator. When negatives come into the picture it gets a little bit harder, you would have to have as always when adding and/or substracting fractions find a commun denominator. Once you’ve got that under control you can then star substracting the two together. Example: – would mean your responds is a positive because you have two negative signes beside each other, which makes your answer a thug a war. (your answer is ).  A negative – negative =positive, positive – negative = negative (thug a war) positive – positive =positive.

Multiplying/dividing fractions

When we were originally thought multiplications it was most likely trough groups. Now because we know our multiplication table we can incorporate it in everyday activity. In high school we are though high school fractions and there proper written form. For example, you have to multiple two whole numbers or fractions together, instead of writing 7 x 7 = 49 you would write (x)(x)=(x); two brackets together already means that it’s multiplying. Multiplying and adding fractions are completely different, however you can also incorporate negatives in. x , you DON’T need to find a commun denominator you just go and multiply the two (or more) numerators together and you multiply the denominators together. Often times you can simplify the numbers and some like to do it during the equation other after they’ve got there answers. When simplifying you can only simplify diagonally, then, simply multiply them together. Negative or positive its always top to top and bottom to bottom! If you are multiplying two negative your answer will be positive, any other time it’s a negative, other than two positives together which stays as a positive.

While you are dividing two fractions together you can also do top to top and bottom to bottom, but you can turn it into a multiplication question because who actually likes dividing ?!? Although you are “dividing” you could just recipicate and turn it into a multiplying question. Example: divided by ; could just be x . How much easier is that ? If you just turn the last number upside down (recipicate), notice that the negative sign stays up on the numerator even though the numerator changed. This only works for division and it works for both negative and positive numbers. When dividing negative with a positive answer is always a negative, when dividing two negatives always a positive and when dividing two positive answer will always stay as a positive.

Other things I learned about rational numbers

Other than the adding/substracting, multiplying/dividing I was also informed about recipicals. Recipicals are a very helpful way to do division with fractions. A recipical number is the opposite of the number you had before. Example: the ricipical would be that fraction flipped, so, . I also learned how to estimate square roots ! Using graph paper is a very easy way to estimate imperfect squares. To start of you write numbers on the paper in ever little box which then eventually forms  a perfect square, after you have reach your goal (number) you than need to count the closest root to your number. Next, count the left over spaces and see how many more you’ll need to get to a perfect square. After you have gotten your numbers put them into a fraction.