Wednesday, January 23, 2008

Ivanne's Scribe Post

Today, we learned how to multiply mixed numbers. Here are the steps in multiplying mixed numbers.

Example:
1 1/4 x 1 1/2

First, you have to convert the mixed numbers to improper fractions.

Denominator x Whole number + Numerator

1 1/4 = 4 x 1 + 1 = 5/4
(4 multiplied by 1 equals 4 plus 1 equals 5. The denominator stays the same.)
1 1/2 = 2 x 1 + 1 = 3/2
(2 multiplied by 1 equals 2 plus 1 equals 3. The denominator stays the same.)

Now, we have 5/4 x 3/2.

Second, you have to multiply the numerators.












5 x 3 = 15

Third, you have to multiply the denominators.












4 x 2 = 8

Now, we have 15/8.

Fourth, we have to simplify the answer. To convert an improper number to mixed number, we have to divide them.












The answer will be the whole number, the remainder will be the numerator, and the divisor will be the denominator. So, we now have 1 7/8.

1 1/4 x 1 1/2 = 1 7/8



We can also use the numerator swap...

Example:
2 1/5 x 1 2/3

We will do the first step...convert the mixed numbers to improper fractions.

2 1/5 = 5 x 2 + 1 =11/5
1 2/3 = 3 x 1 + 2 = 5/3

Now, we have 11/5 x 5/3.

To multiply the fractions easier, we will do the numerator swap.

11/5 x 5/3 will become 5/5 x 11/3.

Now, we have to simplify these fractions.

5/5 = 1
11/3 = 11/3

Our fractions now are 1 x 11/3.

To multiply a whole number and a fraction, you just need to put 1 as the denominator of the whole number.












Now, we have to multiply the numerators..













1 x 11 =
11

And the denominators..












1 x 3 = 3

**Or you can just multiply them like 1 x 1/3 and the answer is 1/3 because any number you multiply by 1, the answer is always the number.

We now have 11/3. We need to simplify them.













So, 2 1/5 x 1 2/3 = 3 2/3

6 comments:

naaadine s. 873 said...

great job ivanne! explanations are very easy to understand!

Michael Jordan 873 said...

good job on your scribe, i really like the way you use the two method and the diagram

mariya 873 said...

wow, i liked how you explained everything. nice use of words.

annedenisse 873 said...

I like your scribe! Very easy to understand with the help of your pictures too.

ruth873 said...

it was very easy to under stand and how you used the pictures to show your work good job.

alexandra873 said...

great job ivanne! keep it up!