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Counting Quadruplets II (Posted on 2010-09-21)

Each of A, B, C and D is a positive integer with the proviso that A ≤ B ≤ C ≤ D ≤ 20

Determine the total number of quadruplets (A, B, C, D) such that: A*B + C*D > 300.

What is the total number of quadruplets (A, B, C, D) such that: A*B - C*D > 100?

See The Solution Submitted by K Sengupta

Rating: 5.0000 (1 votes)

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Subject	Author	Date
solution	Charlie	2010-09-21 17:36:38
precedence / solution	ed bottemiller	2010-09-21 14:05:30

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