All about flooble | fun stuff | Get a free chatterbox | Free JavaScript | Avatars    
perplexus dot info
Home
Welcome to perplexus.info, flooble's perplexing puzzle portal. Here, we collect all sorts of puzzles, from simple logic questions and word tricks to in-depth math problems like probability and geometry. Click around and see if your brain is up to the task! If you're new here, make sure you sign up so that you can leave comments and submit your own problems!
> Logic> Probability> Shapes (1)> General (1)
> Numbers (1)> Games> Paradoxes> Riddles
> Just Math> Science> Algorithms

  
Circles Γ1 and Γ2 ( with centers O1 and O2 respectively ) intersect
at points A and B such that neither center lies on or inside the other circle.
Lines mA and mB are tangent to circle Γ1 at points A and B respectively.

Distinct points C and D lie on Γ2 ∩ H(A,mB) ∩ H(B,mA), where H(X,mY)
denotes the open half-plane determined by the line mY and does not contain point X.

Rays CA, CB, DA, and DB intersect Γ1 at points CA, CB, DA, and DB
respectively.

   I = CADA ∩ CBDB
                and
   J = CACB ∩ DADB

Prove that points I, J, and O1 are collinear.
  
(No Solution Yet, 0 Comments) Submitted on 2018-05-20 by Bractals   
Difficulty: 2 of 5 Bonus: Sum and Product reversal (in Numbers) Rating: 3.50
9+9 is the reversal of 9*9 (18 versus 81)
3+24 is the reversal of 3*24 (27 versus 72)
Find a pair of numbers whose product and sum are reversals of a three digit number.
(Solution Posted, 6 Comments) Submitted on 2006-04-05 by Jer   
Difficulty: 3 of 5SI O NO ? (in General)
Posted on 2018-05-19 by Ady TZIDON (No Solution Yet, 2 Comments)
Difficulty: 4 of 5Will take some time ?? (in Numbers)
Posted on 2018-05-18 by Ady TZIDON (No Solution Yet, 3 Comments)
Difficulty: 4 of 5Just 3 digits (in Sequences)
Posted on 2018-05-17 by Ady TZIDON (No Solution Yet, 4 Comments)
Difficulty: 3 of 5From primes to palindromes (in Numbers)
Posted on 2018-05-16 by Ady TZIDON (No Solution Yet, 4 Comments)
Difficulty: 2 of 5Explain Plato's affinity (in Numbers)
Posted on 2018-05-15 by Ady TZIDON (No Solution Yet, 2 Comments)
Difficulty: 2 of 5What's Seven Got To Do With It? (in Sequences) Rating: 3.00
Posted on 2018-05-14 by Larry (Solution Posted, 2 Comments)
Difficulty: 4 of 5Equally Spaced (in Geometry)
Posted on 2018-05-13 by Bractals (No Solution Yet, 1 Comments)
Difficulty: 4 of 5A reason to complain (in Numbers)
Posted on 2018-05-12 by Ady TZIDON (Solution Posted, 1 Comments)
Difficulty: 3 of 52 capitals (in Word Problems)
Posted on 2018-05-11 by Ady TZIDON (No Solution Yet, 3 Comments)
Difficulty: 4 of 5How about 138? (in Sequences)
Posted on 2018-05-10 by Ady TZIDON (No Solution Yet, 4 Comments)
Difficulty: 3 of 5A Common Number (in Just Math)
Posted on 2018-05-09 by Larry (Solution Posted, 2 Comments)
Difficulty: 2 of 5From NPR (in Just Math)
Posted on 2018-05-08 by Ady TZIDON (No Solution Yet, 1 Comments)
Difficulty: 2 of 5Unique definition (in Numbers)
Posted on 2018-05-07 by Ady TZIDON (No Solution Yet, 1 Comments)
Difficulty: 3 of 5Perpendicular Incenters (in Geometry)
Posted on 2018-05-06 by Bractals (No Solution Yet, 0 Comments)

Recently Posted Solutions:
Difficulty: 2 of 5What's Seven Got To Do With It? (in Sequences)
Submitted By Larry. Solution posted on 2018-05-19 19:41:42
Difficulty: 3 of 5A primer in Malaga (in Numbers)
Submitted By Ady TZIDON. Solution posted on 2018-05-18 17:24:03
Difficulty: 4 of 5A reason to complain (in Numbers)
Submitted By Ady TZIDON. Solution posted on 2018-05-16 12:35:16
Difficulty: 3 of 5190 couples (in Numbers)
Submitted By Ady TZIDON. Solution posted on 2018-05-16 12:33:03
Difficulty: 3 of 5Strongly related (in Just Math)
Submitted By Ady TZIDON. Solution posted on 2018-05-16 12:31:04
Please log in:
Login:
Password:
Remember me:
Sign up! | Forgot password


Search:
Search body:
Forums (0)
Newest Problems
Random Problem
FAQ | About This Site
Site Statistics
New Comments (3)
Unsolved Problems
Top Rated Problems
This month's top
Most Commented On

Chatterbox:
Copyright © 2002 - 2018 by Animus Pactum Consulting. All rights reserved. Privacy Information