Today, we did a test on adding, subtracting, and multiplying fractions.

THE QUESTIONS WERE:

1 1/5 + 3 2/3 =

5 3/4 - 3 5/6 =

7/8 x 4/5 =

2 2/3 x 4 1/2 =

I answered the questions on Microsoft Paint -like application:

1 1/5 + 3 2/3=

For those of you that CAN'T SEE, the writing under the question says: Now make Equivalent Fractions. FOr 1/5 and 2/3, they both go into 15. So multiply numerator of 1 by 3 and the numerator of 2/3 by 5. The denominator will be set at 15.

*Circled areas are answers or part answers.

5 3/4 - 3 5/6 =

STEPS I TOOK:

I (wife) swapped 3/4 and 5/6 to get 5/4 and 3/6. 3/6 is half and 5/4 = 1 1/4.(new question being 6 1/4 - 3 3/6.

Then, I turned 3/6 into 1/2 and did simple subtraction with the wholes. With the fractions, I turned 1/2 into 2/4 to have a common denominator.

The question now is 6 1/4 - 3 2/4. But you can't subtract 2/4 from 1/4, so you need to BORROW a whole from 6 and add it to 4. 1 Whole is 4/4 for this question. So add 4 to 1 to get 5/4. Now you can subtract it with a proper fraction as the answer.

7/8 x 4/5 =

A much faster way to do this is just multiplying and simplifying.

If any of you have caught, i turned 7/5 into a mixed then back to an improper. My mistake, too lazy to fix because i can take half a minute to write this explaining instead of taking a half hour and doing this whole thing again.

7 x 4 is 28

8 x 5 is 40

28/40 ÷ 2 = 12/20

12/20 ÷ 2 = 6/10

6/10 ÷ 2 = 3/5.

Hmmmmmmmm

the answers are different for both strategies. I guess it DOES make a difference if you swap.

2 2/3 x 4 1/2=

Enlarged to view writing.

&*(&*(&(*&(*&(*&(*&(*&(*&(*&&(*&(*&(*(*&(*&(*&(*&(*&(*

Well, thats my scribepost. Took a good 2 hours because i was using this new paint program, which turned out it stunk and wasted my time. , =P ,>_> ,<__<>_<> =o

## Thursday, January 24, 2008

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