slow moving with ratios and proportions...any suggestions?

[Robin in DFW]

Ds12 is using BCM (I have another post regarding MEP:001_smile:). He is having a bit of a hard time with the proportions...setting them up, deciding how to set them up, remembering....

 

Although I like BCM, I do think there might a simpler way to present the information to a younger kid...I mean, these books are for adults/older teens. Oftentimes, the numbers used in the problems are large and he can't seem to get past that. I have let him use the calculator ON A FEW PROBLEMS ONLY...not everything.

 

Is there a program that explains this...ummm...easier??? In kidspeak???

 

Thanks,

Robin

[LittleHouseHomeschool]

4 apples = 20 apples

----------------------------

2 oranges= x oranges

 

Solve the proportion.

 

This proportion is set up properly because all the apples have to be in the numerator portion, while all oranges have to be in the denominator. Apples to apples and oranges to oranges, straight across.

 

Then cross multiply.

 

4x = 20(2)

4x = 40

Then divide by 4 on both sides, to free up the x, so (4x/4 = 40/4)

x = 10

 

Setting the proportion up from a word problem is the hardest part. You just have to get all the parts aligned so that they are apples to apples and oranges to oranges. Labeling the numbers is extremely helpful. And take a lot of time to practice this skill. If he doesn't get this, he will stumble in Algebra big time.

 

Is BCM - Lials Basic College Math? I think Christian Light Education Sunrise Math does a better job of teaching concepts (with all the baby steps) to young people.

 

There is also this little memory trick when you are looking for pieces of a number. You can change this up quite a few ways, but you always solve it the same way.

 

is......%

__ = ___ (Do you see it? is/of = %/100)

of.....100

 

Example:

 

4/8 = %/100 (You can see this better if you can write the fraction clearly over a line)

 

Cross multiply:

 

8x = 4 x 100

8x=400

8x/8 =400/8 (divide by 8 on both sides)

x = 50

 

So 4/8 = 50%

 

I hope this helps.

 

Ah phooey, the formatting won't stay put. I've fixed it as best I can!

Edited June 4, 2010 by LittleHouseHomeschool
The formatting isn't working...

[Crimson Wife]

I haven't personally used it, but what about the Math Mammoth "blue" worktext Ratios, Proportions, and Problem Solving. I have been very impressed by the MM blue workbooks we own.

[Robin in DFW]

ds says he likes the way it looks and can't wait to try it out. He told me he didn't feel comfortable moving forward in his BCM without knowing how to do those pesky proportions a tad better.

 

Thanks for the suggestion.

[motherdear]

you tube for an explanation