Privacy Policy

Terms & Conditions

See Details This website uses cookies. By using this website you are accepting the use of cookies. For more information please view our privacy policy.
Across: DUCK, PLUM, TOES, BALE
Down : DOME, PLUS, CUBE, TALK
Boxes : DUMP, LUCK, SOLE, BEAT
Note : Other anagrams of these words are OK as long as they don't change the answer grid.
Puzzle 451
The BrainBashers mechanical computer is a very sensitive device, it consists of interlocked toothed gear cogs.
The largest cog has 168 teeth and the others have 49, 32 and 15 respectively.
By accident, Daniel started to rotate the largest cog.
How many revolutions must he rotate the largest cog make before the computer is back in its starting position with all of the cogs where they started?
Hint: Try breaking each cog size into prime factors.
Answer: 140 revolutions.
If we break each wheel into its prime factors, we get:
168= 2 x 2 x 2 x 3 x 7
49 = 7 x 7
32 = 2 x 2 x 2 x 2 x 2
15 = 3 x 5
So
revolutions x 168

2 x 2 x 2 x 2 x 2 x 3 x 5 x 7 x 7
revolutions x 2 x 2 x 2 x 3 x 7

2 x 2 x 2 x 2 x 2 x 3 x 5 x 7 x 7
revolutions

2 x 2 x 5 x 7
revolutions

140
Which means revolutions = 140.
Puzzle 452
Starting with the 6 in the bottom left corner, what is the highest total you can make, if you only move up or right, using the mathematical signs on the way?
BrainBashers™ is a trademark. This website uses cookies. By using this website you are accepting the use of cookies. For more information please view our privacy policy. By using this website you are also agreeing to our terms and conditions.