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Counting triplets (Posted on 2010-03-31)

For how many ordered triplets (a, b, c) of positive integers, each less than 10 is the product abc divisible by 20?

See The Solution Submitted by Ady TZIDON

Rating: 4.0000 (1 votes)

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re: Old dog, new tricks?

| Comment 7 of 8 |

(In reply to Old dog, new tricks? by ed bottemiller)

Wolfram's Mathworld is usually a reliable source. Wikipedia's first paragraph on it covers the essentials.

Posted by Charlie on 2010-03-31 17:43:24

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