## Multiply by 5 In Your Head

Multiplying by 5 mentally is easy since you just divide the number to be multiplied by 2 and multiply the result by 10, (also very simple, by just adding 1 zero to the number or if the number has a .5, just move one decimal place to the right).

### Examples:

34 × 5

Thought Process:

1. 34 ÷ 2 = 17

2. 17 × 10 = 170

Therefore, 34 × 5 = 170

63 × 5

Thought Process:

1. 63 ÷ 2 = 31.5

2. 31.5 × 10 = 315

Therefore, 63 × 5 = 315

There are many posts about more sophisticated mental multiplication techniques coming up, though I have to cover the basics first for the sake of completeness.

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## About Edmark M. Law

My name Edmark M. Law. I work as a freelance writer, mainly writing about science and mathematics. I am an ardent hobbyist. I like to read, solve puzzles, play chess, make origami and play basketball. In addition, I dabble in magic, particularly card magic and other sleight-of-hand type magic. I live in Hong Kong. I blog at learnfunfacts.com. You can find me on Twitter @EdmarkMLaw and Facebook. My email is learnfunfacts@gmail.com
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### 25 Responses to Multiply by 5 In Your Head

1. parkinsons95 says:

Helpful! Once again, I needed this years ago. Lol

Liked by 1 person

2. This was handy! Thanks for sharing🤗

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3. Shivangi says:

Wow you are incredible! Thank you for following me… am so happy to follow you back😀

Liked by 1 person

4. Oh! I loved this one. I just didn’t knew this one. Thank you, for sharing such a magical way to multiply anything by 5.

Liked by 1 person

5. Lilly Moore says:

That’s a cool method, I never thought of doing that 🙂

Liked by 1 person

6. parkinsons95 says:

Too late. I need help with grammar, TOO!

Liked by 1 person

• From what I’ve seen from your posts, your grammar is good.

While I’ll never accept even minor grammatical errors on academic papers, it’s not that big of a deal in other types of writings as long as you don’t commit basic errors, and your writings are not ambiguous.

Besides, the English language is a continuously evolving language and it is mostly defined by usage instead of a fixed set of stringent and encompassing rules.

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7. parkinsons95 says:

Where were you when I needed you in my school years??? Lol. This is awesome. Never to late to learn!

Liked by 1 person

• Thanks.

Indeed, we shouldn’t stop learning new things 🙂

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8. Brilliant, Edmark. This method is great for my 10-year old daughter. ᕕ( ᐛ )ᕗ

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9. wandaintn says:

My husband does it this way, but I get confused when I try it. I’ll stick with the way I was taught in grade school, my brain doesn’t handle change very well! 😉

Liked by 1 person

• It doesn’t really matter. We should use the methods that are the easiest for us. That’s why in mathematics, there are so many ways to solve a problem, especially in higher mathi.

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