I need help understanding modular arithmetic. I know that modular arithmetic is instead of going to one o´clock you go to 13 o´clock but Im not sure. I got this off of wikipedia but anyone can put an answer on there. Am I correct? I need help understanding modular arithmetic. Are there multiple modular arithmetic? I need help understanding modular arithmetic.
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Make your question more specific please – John11 Nov 14 '16 at 16:42
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Please look at my profile before voting, answering it or commenting – Nov 14 '16 at 16:42
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How would I make it more specific? – Nov 14 '16 at 16:45
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I don know much more about modular arithmetic – Nov 14 '16 at 16:46
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Modular arithmetic is basically being concerned about remainders. We write $12 \equiv 5 \pmod{7}$ because the remainder when $12$ is divided by $7$ is $5.$ The clock analogy gives a perfect way to picture this.
You're at a Navy hospital, walking around, and you see an announcement for a talk to be given at 1500 hours. What time is that? Well, the military (and some countries around the world) work on a 24-hour clock, so you'd have to work modulo 12. In particular,
$$ 15 \equiv 3 \pmod{12}$$
so you'd go to this talk at 3:00.
There are many tricks to modular arithmetic that are best learned by practice. The best way to learn is by doing, so start small.
Sean Roberson
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In a Navy hospital, 1500 hours is called 6 bells. So 1500 hours is 3 (mod 12) which is 3 mod 4 times two (it advances one bell every 1/2 hour) to make 6. Still an exercise in modular arithmetic but a little more complicated. – hkr Nov 14 '16 at 16:56