math proportions-HELP?

Question

proportions compare two sets of ratios. we have determined that ratios campare 2 numbers or quatities. proportions comepare 2 sets of ratios to determin their equality.

ex:

3/8 =4/12 answer; ?

4/8=10/12 answer ?

4'6=12/16 answer ?

--that is my home work, i dont get it

please help,

thank u

Answer 1

mmm!

Ratio of 3:8 (or 3/8) is not equivalent to 4:8 (4/12)
3/9 is the same ratio as 4/12

4/8 is not equal to 10/12
4/8 = 12/24

I don't know what "4'6" means.

Don't fully understand the question. Hope this helps.

Do you mean 4/8:10/12Here, if you multip the lot by 12 you get
6:10 which simplifies to 3:5 (removing the common factor).

Try multiplying the second by 12, too and the third by 24.

Answer 2

I think these are supposed to be yes/no questions, basically asking "Is this a proportion--yes or no?"

There are two ways you can do this.

Proportions mean you have EQUAL fractions. So, you can just divide the two fractions to see if you get the same answer. 3/8 = .125 and 4/12 = .333... These are obviously NOT equal, so it's not a proportion.

The other way (which is probably what your book says to do) is to multiply the "means" (the two middle numbers), multiply the "extremes" (the first and last numbers), and see if those products are equal. For instance, in 3/8 = 4/12, you get 3*12 = 36 and 8*4 = 32. Since 36 and 32 aren't equal, it's not a proportion.

It turns out NONE of these three examples are proportions, but there may be others in your assignment that are.

Answer 3

false
4/12 = 1/3

false
4/8 = 1/2, 10/12 = 5/6

false
4/6 is the same as 2/3. 12/16 is 3/4

Answer 4

You have to cross multiply to find the two numbers.

For instance, on the first one, you would need to take 8 x 4 and set that equal to 3 x 12. This means 32 equals 36, but the answer would be undefined.

Actually, all of them would just be undefined unless you either had a variable or you meant "minus" instead of "equals".