## Welcome to BrainDen.com - Brain Teasers Forum

 Welcome to BrainDen.com - Brain Teasers Forum. Like most online communities you must register to post in our community, but don't worry this is a simple free process. To be a part of BrainDen Forums you may create a new account or sign in if you already have an account. As a member you could start new topics, reply to others, subscribe to topics/forums to get automatic updates, get your own profile and make new friends. Of course, you can also enjoy our collection of amazing optical illusions and cool math games. If you like our site, you may support us by simply clicking Google "+1" or Facebook "Like" buttons at the top. If you have a website, we would appreciate a little link to BrainDen. Thanks and enjoy the Den :-)
Guest Message by DevFuse

# Replacing Tiles

Best Answer witzar, 12 May 2013 - 12:02 AM

a) How many tiles are ruined on a 4 by 6 floor?
b) How about a 63 by 81 floor?

Spoiler for

Go to the full post

8 replies to this topic

Senior Member

• Members
• 1837 posts
• Gender:Female

Posted 08 May 2013 - 04:15 PM

A rectangular floor is composed of whole square tiles. A diagonal line is drawn (corner to corner) and ruins some of the tiles.
(on a 2 x 5 floor, 6 tiles are ruined, on a 2 x 4, only 4 are ruined.)

a) How many tiles are ruined on a 4 by 6 floor?
b) How about a 63 by 81 floor?
c) Generalize to an m by n floor.

• 0

### #2 bonanova

bonanova

bonanova

• Moderator
• 6161 posts
• Gender:Male
• Location:New York

Posted 08 May 2013 - 04:44 PM

Spoiler for solution

• 0

Vidi vici veni.

### #3 witzar

witzar

• Members
• 233 posts

Posted 08 May 2013 - 04:48 PM

Spoiler for

• 0

Senior Member

• Members
• 1837 posts
• Gender:Female

Posted 11 May 2013 - 07:14 PM

a) How many tiles are ruined on a 4 by 6 floor?
b) How about a 63 by 81 floor?

• 0

### #5 bonanova

bonanova

bonanova

• Moderator
• 6161 posts
• Gender:Male
• Location:New York

Posted 11 May 2013 - 07:39 PM

a) How many tiles are ruined on a 4 by 6 floor?
b) How about a 63 by 81 floor?

Spoiler for looks like

• 0

Vidi vici veni.

Senior Member

• Members
• 1837 posts
• Gender:Female

Posted 11 May 2013 - 07:45 PM

a) How many tiles are ruined on a 4 by 6 floor?
b) How about a 63 by 81 floor?

Spoiler for looks like

6 x 4 should be 2

81 x 63 should be 135

• 0

### #7 bonanova

bonanova

bonanova

• Moderator
• 6161 posts
• Gender:Male
• Location:New York

Posted 11 May 2013 - 07:55 PM

a) How many tiles are ruined on a 4 by 6 floor?
b) How about a 63 by 81 floor?

Spoiler for looks like

6 x 4 should be 2

81 x 63 should be 135

6x4  ruins at least the two corner tiles. Nothing else?

• 0

Vidi vici veni.

Senior Member

• Members
• 1837 posts
• Gender:Female

Posted 11 May 2013 - 09:30 PM

a) How many tiles are ruined on a 4 by 6 floor?
b) How about a 63 by 81 floor?

Spoiler for looks like

6 x 4 should be 2

81 x 63 should be 135

6x4  ruins at least the two corner tiles. Nothing else?

i missed typed 6x4 ruins 8

• 0

### #9 witzar

witzar

• Members
• 233 posts

Posted 12 May 2013 - 12:02 AM   Best Answer

a) How many tiles are ruined on a 4 by 6 floor?
b) How about a 63 by 81 floor?

Spoiler for

• 0

#### 0 user(s) are reading this topic

0 members, 0 guests, 0 anonymous users