Level: elementary and above

Brief description:

These math tricks are designed to have fun while doing some math (of course, practice doing the math tricks in English).

Number 5 Trick

Instructions: Follow the instructions and do the math. If you cannot follow the instructions, use the example below for help.

1. Choose a number from 1 to 10.

2. Double the number.

3. Add 10 to your new number.

4. Now, divide the total by 2.

5. Finally, subtract your original number that you started with.

6. Your answer will always be 5!

Example:

1. Choose a number from 1 to 10.

Ex) 9

2. Double the number.

Ex) 9+9 = 18

3. Add 10 to your new number.

Ex) 18 +10 = 28

4. Now, divide the total by 2.

Ex) 28 / 2 = 14

5. Finally, subtract your original number that you started with.

Ex) 14 – 9 (original number) = 5

6. Your answer will always be 5!

Number 10 Trick

Instructions: Follow the instructions and do the math. Then find a friend to do this trick.

1. Tell your friend to pick a number (any number).

2. Then tell them to double their number.

3. Tell them to add 20 and divide by 2.

4. Then, tell them to subtract the original number they picked.

5. Ask them if their answer is 10. If the math is done correctly, your friend will say yes!

Example:

1. Tell your friend to pick a number.

Ex) 88

2. Then tell them to double their number.

Ex) 88 + 88 = 176

3. Add 20 and divide by 2.

Ex) 176 + 20 = 196 / 2 = 98

4. Then, subtract the original number they picked.

98 – 88 (original number) = 10

5. Ask them if their answer is 10. If the math is done correctly, your friend will say yes!

Glossary:

• Trick (noun): a way of doing something that works very well (Thủ thuật)

• To double (verb): to become twice as much or as many, or to make something twice as much or many (Nhân đôi)

• Original (adj): existing since the beginning, or being the earliest form of something (Thuộc về lúc ban đầu, gốc)

This material is provided by the Australian Centre for Education and Training (ACET).