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Measuring With FractionsMeasuring With Fractions
Take out a clean sheet of notebook paper and something to write with.
Place it in front of you on your desk.
Following DirectionsFollowing Directions
Fold your paper in half long ways “hot dog style”.
Following DirectionsFollowing Directions
Open your paper up and place it holes to the top on your desk.
Draw a line all the way down the crease on the paper.
“DO NOT WRITE ON THE DESK!!”
Following Directions LessonFollowing Directions Lesson
Fold the paper in half the other way “hamburger style”.
You can see my line because I used a Sharpie Marker and it bled through the paper.
Following DirectionsFollowing Directions
Open the paper up with the holes to the top.
Draw a line from the center of the paper to the margin closest to you.
Following DirectionsFollowing Directions
Fold the paper like you had it last “hamburger style”.
Then fold it over again in the same direction as you folded it last.
Following DirectionsFollowing Directions
Open the paper up.
Draw a line on each of the creases half way to the bottom margin.
Then fold your paper back up like you last had it.
Following DirectionsFollowing Directions
Fold the paper over one more time in the same direction as your last fold, making it even more slender.
Following DirectionsFollowing Directions
Open the paper up.
Draw lines on the four creases half as long as the last lines you drew, or ¼ of the way to the bottom margin.
Following DirectionsFollowing Directions
Draw small lines on our paper in between each of the lines already on your paper and the left and right edges.
Make the lines extend down and be half as long as the last lines drawn.
Following DirectionsFollowing Directions
Next, draw lines on the left and right edges all the way down below the margin, half way between the margin and the bottom of the paper.
And in case you haven’t already figured it out, we are making a ruler.
Following DirectionsFollowing Directions
Now all you have to do is count the lines as you go from left to right.
Reading a RulerReading a Ruler
0
1 23
4
56
7
8
910
11
12
1314
15
16
By counting you realize that you have 16 equal parts to an inch.
Next you show each number as a fraction or portion of the total number 16.
Reading A RulerReading A Ruler
0
1/162/16
3/16
4/16
5/16
6/16
7/16
8/16
9/16
10/1611/16
12/16
13/16
14/1615/16
16/16
Next, you must remember from math that a fraction should always be expressed in lowest possible terms.
1/16 for example is in its lowest form, it cannot be reduced any farther.
2/16 however, can be reduced.
2 is the numerator (top number in a fraction)
16 is the denominator (bottom number in a fraction)
Reading A RulerReading A Ruler
2/16 can be reduced by 2. This means that both 2 and 16 are divisible by 2.
2 divided by 2 = 1 16 divided by 2 = 8 Therefore our reduced fraction will be 1/8.
Reading A RulerReading A Ruler
Now lets take 3/16, will it reduce? I bet that someone said yes! Some people look at the three as the numerator
and the six in the sixteen (denominator) and automatically think that this fraction will reduce. However, it will not reduce.
3/16 is already in its lowest terms.
Reading A RulerReading A Ruler
Next, lets look at 4/16. Yes it will reduce. There are two ways to reduce fractions like this one. If you’re a math wiz, you might say that 4 will go into 16. If you do, you are right. You can divide the numerator into the denominator. This is the quickest of the two ways, but you can divided both the numerator and the denominator by 2, twice. You have to be careful to get fractions like this one into lowest possible terms.
Reading A RulerReading A Ruler
The easiest way to deal with 4/16: 4 divided by 4 = 1 16 divided by 4 = 4 Your reduced fraction is ¼.
Reading A RulerReading A Ruler
The other way to deal with 4/16 is: 4 divided by 2 = 2 16 divided by 2 = 8 Your fraction is 2/8, but is it reduced to lowest
possible terms? NO, you have to reduce again. 2 divided by 2 = 1 8 divided by 2 = 4 Your reduced fraction is 1/4
Reading A RulerReading A Ruler
Now that you know how to reduce these fractions, you finish reducing the rest of the fractions on your ruler.
Reading A RulerReading A Ruler
Reading A RulerReading A Ruler
Now Check your fractions against these correct answers.
0
1/161/8
3/16
1/4
5/16
3/8
7/16
1/2
9/165/8
11/16
3/4
13/167/8
15/16
1
Now that you know how to use a ruler, here are some short cuts for you.
As you have noticed, the lines are different lengths on the ruler.
As we go across one more time pay attention to the line length and the denominator associated with it.
Reading A RulerReading A Ruler
0
1/161/8
3/16
1/4
5/16
3/8
7/16
1/2
9/165/8
11/16
3/4
13/167/8
15/16
1
Did you notice a trend?
The longest lines were of course whole numbers.
Reading A RulerReading A Ruler
0 1
The second longest line is 1/2.
Reading A RulerReading A Ruler
The third longest line has a denominator of 4.
1/4
1/2
3/4
The fourth longest lines always have a denominator of 8.
Reading A RulerReading A Ruler
The shortest lines always have a denominator of 16.
1/161/8
3/16 5/16
3/8
7/16 9/16
5/811/16 13/16
7/815/16
Reading A RulerReading A Ruler Now let’s look at
the whole ruler. Can you tell me what would be the correct measurement for the letter A.
The answer is 5-7/16.
You start at the whole number and you add the calculated fraction to the whole number to give the correct distance.
5
A
6
Reading A RulerReading A Ruler What is the correct
measurement for the letter A.
The answer is 10-3/16.
What is the correct measurement for the letter B.
The answer is 10-3/8.
What is the correct measurement for the letter C.
The answer is 10-3/4.
10
A
11
B C
Now you know how to read a ruler and deal with the fractions involved.
But these are measurements, and have to be expressed as measurements. Write the following notes on your paper.
This standard ruler is to be expressed in inches or in. or “. Example: 1 ½”
12 inches is equal to 1 foot or ft. or ‘. Example 4’ 1 ½” Three feet is equal to 1 yard or yd.
15/16
Reading A RulerReading A Ruler
Reading A RulerReading A Ruler
See if you can tell the measurements of the objects on the following screens for a quick quiz.
On the back of your paper title it Measurement Quiz and number from 1 to 5.
Measurement QuizMeasurement Quiz
1.
Measurement QuizMeasurement Quiz
2.
Measurement QuizMeasurement Quiz
3.
Measurement QuizMeasurement Quiz
4.
5.
Measurement QuizMeasurement Quiz
Measurement Quiz AnswersMeasurement Quiz Answers
The answers to the quiz are:
1. 6 - 7/16”
2. 3 – 11/16”
3. 5 – 5/8”
4. 4 – 7/8”
5. 11 – 9/16”