Homeschool Math Blog

A problem about fraction of a fraction... The sixth-graders have a fundraieser. They raise enough money to reach 7/8 of their goal. Nikki raises 3/4 of this money. What fraction of the goal does Nikki raise? The picture below shows first of all 7/8. Nikki raises 3/4 of this goal. We need to find 3/4 of 7/8. It's not easy to directly see what is 3/4 of 7/8. So to do that, I divide each 1/8 piece into four pieces, and then color three of the four. That way I color 3/4 of each of the seven eighths. Of course, those tiny pieces are now 1/32 parts. I have colored 3 x 7 = 21 of them. So, the colored part represents the fraction 21/32. This problem is also simple to solve without a picture, if you understand what is asked. To find 3/4 of 7/8, you simply multiply those two fractions. The word "of" translates into MULTIPLICATION in fraction math!  3 7 21 --- x --- = ---- 4 8 32

I'm just passing on a link that some of you might enjoy (or be sad about). I found it interesting -- a math teacher (Larry Zafran) telling his story of teaching math in an inner city high school in New York in the early 2000s. It appears not much was able to be done but to try to survive and get through the day while presenting the official curriculum topics in class, at least on the board. http://www.larryzafran.com/education-crisis-book.htm

Math Mammoth Thanksgiving sale is already in full swing... You'll get 20% off of all the downloads and CDs sold at Kagi store. To take advantage of this offer, enter the coupon code THANK2010 at checkout. Enter the coupon code on the shopping cart page (not the first order page). Coupon valid till November 29, 2010, only at Kagi store. Not applicable to printed copies. Order pages: Blue series , Golden and Green Series ; Light Blue complete curriculum products ; Packages (CDs or downloads) ; Make It Real Learning workbooks ; Versiones en español .

I just found this via Math Teachers at Play ...   Carolin's Notation for Solving Equations Carolin is a student from Germany. I just wanted to note that that is exactly how I was taught (in Finland) to note what is done to each side of the equation, and I really like the notation. I don't know if it's used in all Europe... Basically, you note in "the right side margin" what you're going to do to both sides of the equation in your next step. The "margin" is made by writing a vertical line to the far right of your actual equation solving process. 6x - 5 = 2x | -2x 4x - 5 = 0 | +5 4x = 5 | ÷4 x = 5/4 I just wanted to pass this on in case some of you who are teaching how to solve equations find it useful with students.

Math Mammoth Statistics & Probability is now available -- and it's the last book I'm intending for the Math Mammoth Blue Series . So the Blue Series is now complete! Price: $5.30 (download), $10.30 (printed) This book starts with the easiest topics, such as reading different graphs . These lessons are meant for 5th grade. Some are useful even in earlier grades. Then we study histograms and various kinds of line graphs , including how to draw them. The next section deals with mean, median, and mode —the three measures of central tendency—how to use them, and how these concepts relate to line and bar graphs. To create circle graphs , the student needs to calculate percentages, and it is assumed here that the student has already mastered how to calculate those. The lesson on data analysis presents various types of graphs for students to read, and reviews some other percent-related topics. Then students learn how to make stem-and-leaf plots . Stem-and-leaf plots ...

Here are two problems for you to solve... OR to learn from me when I solve them. Both problems are for algebra 1, and use a system of 2 linear equations. By the way, the comments have some wonderful ideas for solving these mentally, without using algebra. So please read them too! Problem: John bought red pens for $4 apiece and blue pens for $2.80 apiece. If John purchased a total of 24 pens for $84, how many red pens did he purchase? Solution: This is a typical problem that will have two variables and two equations. Let r be the amount of red pens he buys, and b be the amount of blue pens he buys. We get our first equation from this sentence: "He bought a total of 24 pens." So, r + b = 24. We get the second equation from the fact that his total purchases were worth $84, and red pens cost $4, and blue pens cost $2.80 4r + 2.8b = 84 Now, just solve this system of two equations using your preferred method. r + b = 24 4r + 2.8b = 84 I will multiply the top e...

Here's another one of those job / workers word problems (inverse or direct variation). Try and see if you can solve it using the "table" method instead of equations: A certain job can be done by 18 clerks in 26 days.  How many clerks are needed to perform the job in 12 days? Again, we can set up a table and reason this out. Initially set it up like this: jobs | clerks | days -------------------------- 1 | 18 | 26 -------------------------- 1 | | -------------------------- 1 | ? | 12 Then think of the "days" column. We want to "go" from 26 to 12. You could use a proportion here... or first figure out how many clerks are needed to do this job in 2 days, and then from that go to 12 days. If 18 clerks do it in 26 days, then how many clerks would do it in 2 days... which is 1/13 the amount of time.... so we need 13 times as many clerks. 13 x 18 = 234 clerks are needed. jobs | clerks | days -------------------------...