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How would you like a stack of

$100 bills . . .

No problem . . .

Until you pick up the tape measure or ruler and realize that there is no clear marking for 1 3/8”!

. . . but you could only have the money if you could make the stack of $100 bills 1 3/8” tall.

Now you need to understand how to read a ruler. It’s actually a lot simpler than it looks.

The first thing we need to clarify is the symbols used in measuring. The symbol

' (apostrophe) represents feet.

The

“” (quote) symbol represents inches.

So, the stack of $100 bills 1 3/8” tall is asking for a stack one and three eighths inches tall.

If you were asked to make a stack of $100 bills 1’ 3/8” tall, it would be asking for a stack one foot and three eights

inches tall. That’s a lot of $100 bills!

Now back to understanding all those little marks on the ruler.

1

The longest line in the inch is in the middle. This is the half-inch mark (1/2).

½ + ½ = 1

½

A standard tape measure (or ruler) is divided up into feet and inches.

Each foot is divided into 12 inches.

The problem starts with the subdivision of the inches.

In each inch there are a number of lines of different lengths

The next shortest line is the 1/4" (one quarter of an inch) inch mark and there are only two of these

¼ + ¼ + ¼ + ¼ = 1

1/4 3/4

1

The third shortest line is the 1/8” (one eighth of an inch) and there are four of those.

1/8+1/8+1/8 +1/8+1/8 +1/8+1/8+1/8= 1

Some rulers and tape measures only show measurement to the 1/8 scale. If you need accuracy you will need a ruler or tape measure that can measure 1/16”.

1/8 3/8 5/8 7/8

The shortest line is the 1/16” (one sixteenth of an inch) and there are eight of those.

1

1/16+1/16+1/16+1/16+1/16+1/16+1/16+1/16+1/16+1/16+1/16+1/16+1/16+1/16+1/16+1/16= 1

1/16 3/16 5/16 7/16 9/16 11/16 13/16 15/16

If you count the distance between the inch marks (one inch) you will find sixteen lines. This is because an inch is 16/16th of an inch long. Because we like to express fractional numbers in the largest unit possible we call it one inch. So it follows that if you have 8 lines, or 8/16" you have a half-inch or ½". And likewise, if you have 4 little lines, or 4/16" you have a quarter inch and so on.

8/16

1/2

4/16

¼

1 2 3 4 5 6 7 8

22 443311

1

1/16

2/16

3/16

4/16

5/16

6/16

7/16

8/16

9/16

10/16

11/16

12/16

13/16

14/16

15/16

16/16

sixteenths

or 1/8

or 2/8or 1/4

or 3/8

or 4/8 or

2/4 or 1/2

or 5/8

or 6/8 or 3/4

or 7/8

eighths

8/8

fourths

4/4

half

REVIEW

1

1/16

1/8

3/16

1/4

5/16

3/8

7/16

1/2

9/16

5/8

11/16

3/4

13/16

7/8

15/16

2

When measuring, you would not say the red line is 4/16 of an inch long or 2/8 of an inch long,

but ¼ of an inch long.

Measurement of fractions are always said in their lowest common denominator

1

1/16

1/8

1/4

5/16

3/8

1/2

9/16

5/8

3/4

7/8

Find ¼Find 5/8Find 5/16

Find 1/2

Find 3/4Find 1/8Find 9/16Find 7/8

Find 1/16

Find 3/8

REVIEW

1 2

REVIEW

a) 5/8 b) 9/16

c) 3/4 d) 11/16

What is the length of the red line?

1 2

REVIEW

What is the length of the red line?a) 1 1/4 b) 1 1/16c) 1 1/8 d) 1 3/16

1 2

REVIEW

What is the length of the red line?a) 7/8 b) 3/4

c) 1 1/8 d) 1 7/16

1 2

REVIEW

What is the length of the red line?

a) 1 1/4 b) 1 3/8

c) 1 1/2 d) 1 7/16

1 2

REVIEW

What is the length of the red line?a) 1/4 b) 3/8

c) 1/2 d) 7/16

1 2

REVIEW

What is the length of the red line?

a) 1 3/4 b) 1 3/8

c) 1 5/16 d) 1 13/16

1

1/16

1/8

3/16

1/4

5/16

3/8

7/16

1/2

9/16

5/8

11/16

3/4

13/16

7/8

15/16

1/2

2

1/16

1/8

3/165/16

1/4

3/8

7/16 9/16

5/8

11/16

3/4

13/16

7/8

To get your stack of 100 dollar bills, click on the 1 3/8” mark on the ruler

THAT’S RIGHT!

15/16

See your instructor for a stack of $100 bills so you can measure 1 3/8”.

CLICK

For more measurement practice

CLICK HERE TO PLAY

THE RULER GAME

www.rickyspears.com/rulergame

Please wait while this program erases the hard drive.

Just kidding!

The program should load momentarily depending on your connection speed.

Click twice to end program..