Practice

[chrishuff]

So recently I have been practicing some of the newer NS tests... They sure have gotten much harder as time goes on!

For example:

2010 District 1


15.
3 (3/4) pecks is equivalent to ____ quarts (What?! Uncommon units!?)

*20. The square root of 8679 is

21.
0.120120120 (proper fraction)

Other problems I have include, but are not limited to:

I "am not talented" at multiplying two square roots together, big and small - Math Magic's lesson is only making me stress out
Memorizing the different types of numbers to solve problems such as #22 on the District 2010 test
Cubing numbers (If there is a way besides memorization, that will be great)

[nsguy1350]

Keep practicing! You will be a legend if you make it to State in NS like this! You will be my example to anyone who says that aren't a NS person, or s-uck too much at it to try. :D
I'm here all the way man.

15. You have to know that a peck = 2 gallons and a bushel = 4 pecks. That's as high as you need to go. Go from teaspoons to bushels.
8 x (3 3/4) = 30

20. Take off 2 digits from the right at a time, and add zeroes at the end, 2 per couple of zeros (three if cube root, 4 is fourth root, etc.)
When you get your truncated number (2-3 digits usually), approximate that and then add your zeros.
[unparseable or potentially dangerous latex formula].
I guessed 9.4 because it's sqrt{87} is a little above 9, but quite a bit less than 10. A linear approximation (halfway ~ add .5) is perfectly fine for these problems. Don't spend too much time with the decimal you multiply by.

21. See the 3 repeating? 1 repeating = 1/9, 2 repeating = 1/99, 3 repeating = 1/999.
This is complicated when you add non-repeating digits to the beginning of the decimal, such as .1234343434, where 12 is non-repeating but 34 is repeating.
If there are no repeating digits, like in this problem, put it over 999. 120/999 = 40/333.
If there are non-repeating digits, like in .122222222 or .1233333333 or .1234343434, then take the portion that is non-repeating (respectively, the 1, the 12, then the 12),
subtract it from the non-repeating digits added to one series of the repeating (respectively, 12 - 1, 123-12, 1234-12), then put it over the denominator which you are abot to determine.
To determine the denominators, remember that in the denominator, 9s are first, and 0s are second. You'll always see things such as 1/999, 1/990, 1/90, 1/900, but never 1/909 or 1/9009. For every digit that is repeating (respectively, 1,12, and 12 have 1, 2, and 2), know that that is how many 9s you have. Every non-repeating digit is how many zeros. Remember that although 9s are first in the denominator, they are first in the decimal (.12343434.... -- 0s determine 12, which is first, 9s determine 34, which is second).
The answers to the examples above are [unparseable or potentially dangerous latex formula]. Hopefully 611/4500 can't be simplied any further, or else I'm wrong. You don't see decimals that big, though, usually.

Memorize the first 10 square roots to three decimal places (I have 2 decimals, I need to get 3, though. 3 are free - 1,4,9). Truncate means round down. Notice how [unparseable or potentially dangerous latex formula], so just round [unparseable or potentially dangerous latex formula] down to 2.4.
Go to http://www.dentonisd.org/51233829152830 ... 0&C=110089 and go to "Types Of Numbers". There are a few tips I can give you if you need help. By the way, if anyone can determine lucky numbers quickly, help is appreciated! :D
If you're asking 9^3, you SHOULD know that instantly. Sorry, you're going to have to memorize. Up to 20-25 is fine for cubes.
Hopefully no mistakes!!! Tell me if I made one, or you think I did.