Multiply with Number Line Models uses Number lines to demonstrate multiplication of fractions.

You can input the two factors for a multiplication of fractions example. The first factor must be less than 6 and the second factor must be less than 4.

If you want just a whole number for the first or second factor, type in 0 (zero) for a numerator. If you do not want a whole number, type in 0 (zero) for the whole number. Do not type in 0 for the denominator.

With this program you can demonstrate a mixed number times a mixed number.

Uncheck the <EXPLAIN> check box to turn off the answer and the explanation. You can ask your students to complete the number sentence.

Uncheck the <SHOW INPUT> check box to make the input dialog boxes work like a password input boxes, hiding the numbers you input. With <EXPLAIN> and <SHOW INPUT> unchecked you can ask your students to write a number sentence that explains the picture.

With <EXPLAIN> and <SHOW COLOR> unchecked you can ask your students to complete the picture by drawing a line for each factor and shading the product.

Suggestions:

Demonstrate a number pattern. For example, put in a first factor of 1 1/2 X 1/2. You can tell by the image that you get 1/2 + 1/4 for a product. Then multiply 1 1/2 X 1 (use zero (0) for numerator of second factor) and you will see 1 1/2 for a product. This demonstrates the identity for multiplication (1). Continue with 1 1/2 X 1 1/2 giving you a product image of 1 + 1/2 + 1/2 + 1/4 0r 2 1/4. Continue increasing the second factor by 1/2 to see how the product increases by 3/4 each time you increase the second factor by 1/2.

Demonstrate reciprocal (multiplicative inverse) by multiplying a number by its reciprocal. For example, 3//2 X 2/3. You may put in Zero(0) for whole number or just leave the whole number blank. You will get 1 for a product. This demonstrates a central idea in our number system - that the product of two reciprocals is one(1)

You can demonstrate 1 as the identity for multiplication by using 1 X 2 2/3 (use zero (0) for a numerator) You will get a product, of course, of 2 2/3.

Demonstrate 0 as a factor. Leave the whole number and the numerator blank in the first factor. Look how flat the product is.

Finally, for the algebra students. Try 2 1/2 X 2 2/3. Remember multiplying a binomial times a binomial? Here's your chance. (2+ 1/2)(2+2/3) = 2X2 + 2X2/3 + 1/2X2 + 1/2X2/3 = 4+4/3+ 1 + 1/3 for a product of 6 2/3. It's in the picture. Use the FOIL method here, if you wish.

WINDOWS™ COMPUTERS

You may copy the screen by pressing <Print Screen> on the keyboard. This copies the screen into Windows Clipboard™. The screen can then be pasted into Windows Paint™ or your favorite imaging program. Windows Paint™ will allow you to crop, print or save the image.

Windows 7 users can use the Snipping Tool™ to capture any part of the screen you wish. These images can be edited and saved in PNG, GIF(recommended) or JPEG formats.