A Basic Multiplication Question (Common Mistake)

Site: http://www.kiasuparents.com/kiasu/forum/viewtopic.php?f=29&t=71476&p=1377930#p1377930

HermioneGranger wrote:

Hi, a desperate question.In solutions of equation, when you multiply 2(2) by two, why is the answer 2(4) and not 4(4)?

TIA :)

Good question!

The theoretical reason is that if we multiply a product a(b) by two, we are actually having two copies of a(b).

Hence, 2 x a(b)= 2 times of a(b) = 2a(b) = a(2b)

For a concrete example, think about what would happen if we multiply 1(1)(1)(1)(1) by 2.

1(1)(1)(1)(1) is just 1, hence the answer should be 1(1)(1)(1)(2)=2, and not 2(2)(2)(2)(2) which is 32.

Featured book:

Math Doesn’t Suck: How to Survive Middle School Math Without Losing Your Mind or Breaking a Nail

Author: mathtuition88


Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

This site uses Akismet to reduce spam. Learn how your comment data is processed.