Mental Math Trick for Multiplying by 11

In this video, Mr. Jay introduces a mental math trick for multiplying two-digit numbers by 11. The trick involves splitting the digits of the number, adding them, and placing the result in between. The video provides examples with numbers like 53, 27, 48, and 95, demonstrating the process and explaining the concept of carrying when necessary. The video concludes with a summary of the trick and its usefulness.

What is the main purpose of the mental math trick discussed in the video?

• To make multiplication faster

• To provide an alternative method for multiplying by 11

• To improve addition skills

• To replace traditional multiplication methods

Tags

TEKS.MATH.4.4D

In the 'split and add' method, what is the result of 53 times 11?

• 511

• 530

• 553

• 583

When using the 'split and add' method, what do you do after splitting the digits?

• Add them

• Divide them

• Subtract them

• Multiply them

Tags

TEKS.MATH.4.4D

What is the result of 27 times 11 using the 'split and add' method?

• 297

• 217

• 287

• 277

Tags

TEKS.MATH.4.4D

In the example of 48 times 11, what is the correct way to handle the sum of 4 and 8?

• Ignore the carry

• Place 2 in between and carry 1

• Place 1 in between and carry 2

• Place 12 in between

Tags

TEKS.MATH.5.3B

What is the final result of 48 times 11 using the 'split and add' method?

• 528

• 548

• 538

• 518

Tags

TEKS.MATH.4.4D

In the example of 95 times 11, what is the result after carrying over?

• 945

• 955

• 1045

• 1055

Tags

TEKS.MATH.2.4B

What is the first step in the 'split and add' method?

• Multiply the digits

• Subtract the digits

• Split the digits

• Add the digits

Tags

TEKS.MATH.4.4D

Why might someone choose to use this mental math trick?

• It is required for all math tests

• It is a fun and interesting method

• It is the only way to multiply by 11

• It is faster than using a calculator

Tags

TEKS.MATH.5.3B

What is the key phrase to remember for this mental math trick?

• Multiply and carry

• Subtract and multiply

• Divide and conquer

• Split and add

Tags

TEKS.MATH.5.3B