Jomari's Post November 14,2010

Question 21: Calculate the Following
A. 1/3(2/5 - 1/2) + 3/10
B. 3/4÷5/8 - 3/8 ÷ 1/2
C. 1 1/2 + 1 1/2 (-2 2/6 + 1/3)

A.)
1/3(2/5 - 1/2) + 3/10
1/3(4/10-5/10) + 3/10
1/3(-1/10) + 3/10
-1/30 + 3/10
-1/30 + 9/30
8/30
4/15

B.)
3/4÷5/8 - 3/8 ÷ 1/2
6/5 - 3/4
24/20-15/20
9/20

C.)
1 1/2 + 1 1/2 (-2 2/6 + 1/3)
1 1/2 + 1 1/2 (-2)
1 1/2 + -3
-2 1/2

When we do these questions, we just remember BEDMAS to do everything in order.
Please comment and tell me how to improve my post.

April's Scribepost

Once again, the whole class was assigned a question from the textbook. My question was from 2.3, page 68, #5.

5) Estimate and Calculate

Thank you for reading my post. Please leave a comment. :)

Question 22

Taj has three scoops for measuring flour. The largest scoop holds 2 1/2 times as much as the smallest one. The middle scoop holds 1 3/4 times as much as the smallest one.

Describe two different ways in which Taj could measure each of the following quantities. He can use full scoops only.

a) 3 1/4 times as much as the smallest scoop holds.

First off, i figured that the smallest scoop is 1, or 1/1.

To get 3 1/4 as much as the smallest scoop, I changed the fractions into decimals, so i ended up with

large scoop:2.5

medium scoop:1.75

small scoop:1.0

I then changed 3 1/4 to a decimal and got 3.25.

The two answers I came up with were:

1.large scoop (2.5) + medium scoop (1.75) - small scoop (1.0) = 3.25

2.two large scoops (5) - medium scoop (1.75) = 3.25

b)1/2 as much as the smallest scoop holds.

1.two large scoops (5) - two medium scoops (3.5) - one small scoop (1.0) = 0.5

2.two medium scoops (3.5) - three small scoops (3) = 0.5

if u have ne suggestions plz comment

Kamille's Scribepost

HELLO, This is kind of late but anyway.. but we we're assigned a question to do and i had to do question 19 so let's get right to it.

QUESTION 19.











a) - 5 /4 b) 11/10 c) 16/13 d) - 3/2

Elijah's ScribePost for November 13, 2010

For Math, my question was number 17, Chapter 2.3

17. To calculate -3/4 + (-2/3), Amy decided to convert the fractions to decimals and add the decimals on a scientific calculator.

a) Explain why she had difficulty in determining the exact answer by this method.
For Amy's method, she wanted to turn - 3/4 and -2/3 into decimals and just add them up.

If you convert - 3/4 into a decimal it would be - 0.75.


If you convert - 2/3 into a decimal it would be -0.6 repeating.

If you add those two up you can't get the exact answer because there is a repeating decimal in the question.

b) How should she calculate to get an exact answer?

Amy should just stick with adding it the fractions method.

- 3/4 + (-2/3)=

Well first you have to find the common denominator for the fraction. Their common denominator is 12. And how do you turn the denominator ( 4 ) and ( 3) to 12 ? You multiply 4 by 3 and you multiply the 3 by 4. Now the fractions denominator is 12. But you also have to do the same to both fractions numerator. So you multiply the 3 by 3 which is 9 and multiply the 2 by 4 which is 8. The fractions are now -9/12 and -8/12. Then you just add the 9 and 8 together and which becomes the numerator and the denominator stays the same.

Sharmaine's Scribe Post for Novermber 12, 2010

Hi everyone! In math class we were assigned to do question in the textbook. I was assigned to do question 25 on page 70.

The question was:

The following expression has a value of 1
[- 1/2 + (- 1/2)] / [-1/2 + (-1/2)]

Use - 1/2 four times to write expressions with each of the following values.

a) -1 b) 0
c)1/4 d) 4
e) - 3/4 f) -1 1/2

What i did to figure out if my answer was correct i simply changed -1/2 in a decimal which would be -0.5.

a) [-1/2 + (- 1/2)] + [-1/2 - (-1/2)] = 1

-0.5 + -0.5 = -1
-0.5 - -0.5=0
-1 + 0 = -1

b) [-1/2 - (-1/2)] - [-1/2-(-1/2)]= 0

-0.5 - -0.5 =0
-0.5 - -0.5=0
0-0=0

c)[-1/2 x (-1/2)] - [-1/2 - (-1/2)]= -1

-0.5 x -0.5 = 0.25
-0.5 - -0.5 = 0
0.25 - 0 = 0.25
but in fraction form it would be 1/4

d) (-1/2) / (-1/2) / (-1/2) / (-1/2)= 4

-0.5 / -0.5 / -0.5 / -0.5 = 4
-0.5 / -0.5 = 1
1 / -0.5 = -2
-2/ -0/5 = 4

e) [-1/2 + (-1/2)] + [-1/2 x (-1/2)]= -3/4

-0.5 + -0.5 = -1
-0.5 x -0.5 = 0.25 or 1.4
-1 + 0.25 = -0.75 or -3/4

f) (-1/2) / (-1/2) / (-1/2) - (-1/2) = -1 1/2

-0.5 / -0.5 / -0.5 - -0.5 = -1.5 or -3/2 or -1 1/2
-0.5 / -0.5 = 1
1 / -0.5 = -2
-2 - -0.5 = -1.5 or -3/2 0r - 1 1/2

PLEASE COMMENT AND CORRECT ME IF I HAD ANY MISTAKES

Michelle's Scribepost for November 9,2010

Hey everyone! Today in class we were given questions from the textbook. I had to do question 6 from 2.3.

First you find the common denominator. Sometimes when you multiply both denominators you can find the common denominator, but that doesn't always work because you want the least common denominator. For example, in questions b), d), and e) If you multiplied both the denominators, the denominator would be a big number. So you have to find the least common multiple.

The next step is, whatever you do to the bottom (denominator), you do to the top (numerator).

*Refer to a) Think how many times does 3 go into 12? 4 times, so you have to multiply both the numerator and denominator by 4. (2 x 4 = 8) Also with the other fraction (3/4), you find how many times does 4 go into 12? 3 times, so you multiply the denominator and numerator by 3.

Then after you changed the fractions which are now equivalent fractions, (still referring to a) you minus (or add, depending on the question) the numerators. (8-9= -1) and keep the denominator the same.

In question e) there are mixed fractions. One way to change mixed fractions into improper fractions is by, multiplying the denominator by the whole number and adding the numerator to get the NEW numerator. Keep the denominator the same.

In question f) you can just take the whole numbers and fractions and separate them. First you do the whole numbers 1 + (-1) = 0. Then you do the fractions like you would normally do it.

Sorry if this doesn't really make sense, I tried to explain it. And sorry for lack of colours, it doesn't work.

Noelle Cuvos' Second Awesome Blog Post

So this is whats up, we all had to do a question from 2.3 and show our answers on the blog. So i had question number 4 from the History Link section from page 71.

4. Express each of the following as the sum of three unit fractions without using any fraction more than once.

a) 7/8 = 1/2 + 1/4 + 1/8

1/2 = 4/8

1/4 = 2/8

1/8 = 1/8

7/8

b) 11/24 = 1/4 + 1/8 + 1/12

1/4 = 6/24

1/8 = 3/24

1/12= 2/24

11/24

c) 3/4 = ?

Well for letter C, I couldn't find an answer after a while thinking about it. So comment and tell me what you got and how you got it, Thanks. peace !