"Review of Numbers Represented by Letters" PPT

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"Review of Numbers Represented by Letters" PPT

Part One: Teaching Objectives

1. Review and organize the knowledge about using letters to represent numbers in primary school. Through review, students can use letters to represent numbers in specific situations. Able to use letters to express operation laws and calculation formulas.

2. Let students go through the process of exploring rules and use letters to represent certain rules, experience how using letters to represent numbers can express general rules, and enhance the awareness of applying rules to solve problems.

3. In the process of using letters to represent numbers, students can appreciate the simplicity of using letters to represent numbers, further enhance their awareness of conformity, and develop their ability to abstract and generalize.

Review PPT on using letters to represent numbers, part 2: the rules of how letters represent numbers

What other laws in life can be expressed by n²?

How to abbreviate or abbreviate expressions containing letters? What to pay attention to?

Use letters to express common quantitative relationships, operation laws and properties, and calculation formulas for geometric figures.

(1) Common quantitative relationships, such as:

The distance is represented by S, the speed is represented by v, and the time is represented by t.

The relationship between the three: S＝vt v＝S÷t t＝S÷v

(2) Operational laws and properties

For example: the associative law of multiplication: (ab)c=c(ab)

Distributive law of multiplication: (a+b)c=ac+bc

Subtraction: a-(b+c)=a-b-c

Review PPT on using letters to represent numbers, part 3: write about it

Can the operation symbols in the following expressions be omitted? If possible, write down the omitted formula.

n×5 a×c 1×m

c×c n－9 m×9×n

When using letters to represent numbers, there are some rules that you should pay attention to in writing:

(1) When multiplying numbers and letters or letters and letters, the multiplication sign can be written as "." or omitted, and the numbers should be written in front of the letters.

(2) When "1" is multiplied by any letter, "1" is omitted and not written.

(3) In a question, the same letter represents the same quantity, and different quantities are represented by different letters.

Review PPT on using letters to represent numbers, part 4: fill it in

1. The number that is 25 less than x is ().

2. The difference between 5 times n and m is ( ).

3. A shirt costs a yuan, and a sweater costs 6 yuan, which is twice as much. The price of the sweater is ( ) yuan.

4. The original price of a product with a 20% discount is ( ) yuan.

Thinking questions

In the picture,

(1) Which part has an area ac?

(2) Which part has the area bc?

(3) How to calculate the area of ​​the entire figure?

Keywords: Free download of Hebei Education Edition mathematics PPT courseware for sixth grade volume 2, review PPT download of using letters to represent numbers, .PPT format;

For more information about the "Review of Numbers Represented by Letters" PPT courseware, please click the Review PPT Courseware Represented by Letters.

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Update Time: 2024-07-04

This template belongs to Mathematics courseware Hebei Education Edition Sixth Grade Mathematics Volume 2 industry PPT template

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