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Missing digits (Posted on 2004-09-04) Difficulty: 2 of 5
Multiplying three consecutive even numbers gives 87*****8, where each "*" stands for a digit. What are the missing numbers?

See The Solution Submitted by Federico Kereki    
Rating: 2.2857 (7 votes)

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Solution Cube Roots | Comment 4 of 9 |

Of the consecutive even digits (0,2,4,6,8), taken as consecutive triples,
only 2, 4 and 6 will produce a product of 8 as the units digit.
As three consecutive even numbers are required to produce 87*****8, I assumed
the cube root of 8800000 (which is > 444).  Then I considered the cube root of
87000000 (which is > 443). 

This suggests that 444 is the middle of the three numbers (ie 442, 444 and 446);
the product is 87526608.

Missing numbers are therefore 52660


  Posted by brianjn on 2004-09-04 21:07:17
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