This discussion board is a place to discuss our Daily Challenges and the math and science
related to those challenges. Explanations are more than just a solution — they should
explain the steps and thinking strategies that you used to obtain the solution. Comments
should further the discussion of math and science.

When posting on Brilliant:

Use the emojis to react to an explanation, whether you're congratulating a job well done , or just really confused .

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Try to contribute something new to the discussion, whether it is an extension, generalization or other idea related to the challenge.

Stay on topic — we're all here to learn more about math and science, not to hear about your favorite get-rich-quick scheme or current world events.

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Easy Math Editor

This discussion board is a place to discuss our Daily Challenges and the math and science related to those challenges. Explanations are more than just a solution — they should explain the steps and thinking strategies that you used to obtain the solution. Comments should further the discussion of math and science.

When posting on Brilliant:

`*italics*`

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boldNote: you must add a full line of space before and after lists for them to show up correctlyparagraph 1

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`\boxed{123}`

## Comments

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TopNewestYou have until next Monday, $3:00$pm!

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Step 1) The first statement implies that the possible digits of N are 0, 1, 4, 6, 8, and 9.

Step 2) The first statement implies that N is divisible by 2, 3, 5, and 7.

Step 3) Because 2 and 5 divide N exactly, 10 must also divide N. This implies that the last digit of N is 0.

Step 4) Now, lets try listing some positive integer that divisible by 3, 7, and 10.

Notice that 840 is the smallest positive integer that satisfy the statement.

PS : I notice that the third step is not necessary, but it might give you insight on other problem.

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Correct, but slightly different method.

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