Message Font: Serif | Sans-Serif
 
UnThreaded | Threaded | Whole Thread (21) | Ignore Thread Prev | Next
Author: DrtThrwingMonkey Big gold star, 5000 posts Old School Fool CAPS All Star Add to my Favorite Fools Ignore this person (you won't see their posts anymore) Number: of 18426  
Subject: Re: What is 47X63? Date: 2/12/2013 8:09 AM
Post New | Post Reply | Reply Later | Create Poll . Report this Post | Recommend it!
Recommendations: 1
But to be clear -- the ability to do math in one's head while a good tool to have (even if just to get a date) is exactly the opposite of what I was saying.


I was thinking, you could also do 47 x 63 by taking out one of the factors of 63, say the 3 or the 7. For instance, 47 x 21 x 3, the first two are not hard to do in your head, 940 + 47 = 987, the multiply by 3. Using goofy's idea, that would be 3000, less the 3 x 13 that is in excess, giving you 2961.

Or you could do 47 x 9 x 7, again with goofy's method (works well with numbers close to 10, the first part is 470 - 47 = 423, then 423 x 7 is easier to do than 2 digits by 2 digits, essentially 2800 + 140 + 21 = 2961.

Regards, DTM
Post New | Post Reply | Reply Later | Create Poll . Report this Post | Recommend it!
Print the post  
UnThreaded | Threaded | Whole Thread (21) | Ignore Thread Prev | Next

Announcements

2013 Feste Award Voting Begins!
Who will win the 2013 Feste Award? Vote now for the Fool that most exemplifies the Fool Community mission of Learning Together!
When Life Gives You Lemons
We all have had hardships and made poor decisions. The important thing is how we respond and grow. Read the story of a Fool who started from nothing, and looks to gain everything.
Post of the Day:
Tax Strategies

TMFPMarti-Feeling Good
What was Your Dumbest Investment?
Share it with us -- and learn from others' stories of flubs.
Community Home
Speak Your Mind, Start Your Blog, Rate Your Stocks

Community Team Fools - who are those TMF's?
Contact Us
Contact Customer Service and other Fool departments here.
Work for Fools?
Winner of the Washingtonian great places to work, and "#1 Media Company to Work For" (BusinessInsider 2011)! Have access to all of TMF's online and email products for FREE, and be paid for your contributions to TMF! Click the link and start your Fool career.
Advertisement