Math problem

<p>Okay so what is the shortest way to solve this thing?</p>

<p>For all positive integers A, let [A] be defined as the sum of the odd integers from 0 to A, inclusive. For example, [8] = 1+3+5+7 = 16. What is the value of [100] - [96] =?</p>

<p>and also in problems such as this: How many positive integers less than 1000 are NOT divisible by 3? - is the right way to solve it to divide 1000 by 3 and then deduct the result from 1000? Or it just happened that solving it like this for this problem gave me the right number.</p>

<p>It would seem for the first one you just add 97 + 99 to get the difference. Look at the equation. If the two numbers were [96] - [96]. you would have zero. After 96 to get to 100 you use only two odd numbers, 97 and 99. As to second question, I believe that method works.</p>

<p>Of course, you’re right. Excuse me while I headdesk myself to death. Its funny how I always get stuck on the easy questions,whereas the hard ones are no problem! haha</p>

<p>The question that took me the longest time to figure was the question which asked me the ratio between a circle’s diameter and its radius.</p>

<p>My first 30 seconds was spent on thinking ‘What? Is this the right question?’
Then the next 30 seconds: ROFL
Next 30 seconds: Hmm, 2, or 0.5?
Next 30 seconds: ZOMFG! I don’t know!!!
Next 30 seconds: *dies
2:30-3:00: I decide that the answer is…</p>

<p>Lol.</p>

<p>LOL I’m guessing you solved it eventually? XD</p>

<p>Well, I’m still waiting for my test results, but my answer was 2. I hope that’s correct.</p>

<p>both of them have until 95,so the difference starts at odd number 97,97+99=196</p>

<p>196</p>

<p>I just saw it after 2 mins. </p>

<p>What book was this question from?</p>