That type of Math questions...

Test Preparation SAT Preparation
1

<p>Hey, I'm new here and I recently took the Oct test.
On my practice tests I usually scored 800 on Math, had about 6 mistakes in CR overall and around 3 in writing (sometimes a little more...) [btw do you guys know if this would be enough for a score of 2300?]</p>

<p>Anyways, on the Oct test I kind of freaked out and I don't think I did so well, so I decided to do it again in November just in case, I need a high score. But there is this type of question that I didn't really see a lot on the practice tests and I couldn't answer it (efficiently, at least) on the test... It's the type of question that goes like that:</p>

<p>How many integers with a particular property are there between this number and that number...</p>

<p>Like, on the last test there was something with 600... How many integers that are multiples of something are there between 0 and 600... I can answer it, but it takes a long time and there must be a more efficient way than counting them lol...</p>

<p>Another question I managed buy found a little... weird, was the question with the difference between of the sum of all positive integers up to 96 and sum of all +ve integers up to 100... Are we supposed to use that formula for sequences? Or is there an easier way...?</p>

<p>Oh! Before I forget, I have one more question. I thought that the Oct test would be my last SAT test, so I used all of the real tests I had from the blue book. I also did the practice test on the college board site. Now I don't have any real tests to practice with and I really need some new (for me,) original CR sections to do... Any idea where can I find that? I don't really have time to buy books as I live in Asia and I have to order the books online - takes way too much time...</p>

<p>Anyways, thanks a lot for the repliers :)</p>

2

<p>

</p>

<p>I’m in Turkey and Amazon took me less than a week.</p>

<p>I’m afraid I can’t answer your other questions.</p>

3

<p>See if you can pick up a pattern. E.g., one of the questions I think you are referring to was how many positive integers less than 1000 are not multiples of three. The integers in question are 1, 2, 3, …, 997, 998, 999. Multiples of three are 3, 6, 9, …, 999, which occur every third number. With 999 total numbers, 333 are multiples, and 666 are not.</p>

<p>For the sum question, the first sum is 1+2+…+ 96, the next sum is 1+2+3+…+96+97+98+99+100. These two sums are the same except for the last few numbers. If you subtract the sums, everything cancels except 97+98+99+100.</p>