Quincy,

It is true.  The webmaster is Dewayne Jones which is me.  And yes I could finish a test in about 6 minutes.  But I would NEVER suggest doing that.  I only did it just to see how fast I could do it, but I made a lot of mistakes (I only did it one time and that was during my own personal practice.  My teacher was NOT impressed.  In fact I got scolded pretty good.  I only made a 274 which is not good.)  The only way to do this though is lots of practice.  In high school I was a bit of a nerd and practised during the summers.  I used to do about 5 tests a day.  When you do it so much, you learn to recognize problems without having to really think about them.

As far as the test B goes, I don't have it yet.  Like the website says I always get my tests off of texasmath.org.  So I won't have it until he has it.  (I am not in Texas now, so getting the tests are difficult). 

Now for your questions.  I will tell you how I would approach them.  The first problem is meant to distract you using the same numbers.  Actually, there is not an easy shortcut but you can change it a little to make it much easier on yourself.  First, take only digits at a time and rearrange according to the sign.  So for the problem 458 - 584 + 845, we need to work starting with the ones digits only.  So think of this as being (8 + 5 - 4).  Notice that I put the subtraction at the end.  Evaluating we get 9.  Write 9.  Then take the tens digits (5 + 4 - 8).  Evaluating we get 1.  Write 1.  Now the hundreds digits (4 + 8 - 5).  Evaluating we get 7.  The answer is 719.  Don't let these type of problems throw you off.  That is what they are designed to do.

The next problem is sales tax.  All you have to do is multiply the percent by the dollar amount.  But be careful.  They almost always make the problem where there is a 0 on the end.  In this example we multiply 65 * .04  (since 4% = .04 as a decimal).  You should be able to do this fairly quickly but you MUST be careful.  You will notice that 4 * 5 = 20.  20 has a 0 on the end, so you might not write that down.  In this example 65 * .04 = 2.6.  Since it is a money problem you can write $2.60 but most of the time they will make the problem so the last 0 will be cut off and you will get the problem wrong if you write 2.60.

The next problem is using logs.  The trick is to make an equation that is simple to solve.  In the problem log9 243 = ? we can change this (using the properties of logs) to 9^? = 243.  You need to recognize that 243 = 3^5.  (That is why it is good to memorize your higher powers!!!)  So now we can make this 9^x = 3^5.  (Notice I just changed the ? to an x).  This is still not simple since we need the bases to be the same so we can make a simple equation.  So we need to change something.  Look at 9^x.  We can change this to have a base of 3 by changing 9 to be 3^2.  If we do this we now have: (3^2)^x = 3^5.  Using properties of exponents this is simply 3^(2x) = 3^5.  For this to be correct, 2x = 5.  Now we have a simple equation and can get the answer 5/2.  I used a lot of words to explain this but this trick is actually very fast.  Practice with some more problems like this and you will gain a lot of speed.

Now for the last question.  This log problem is VERY simple.  You should know that (logA B) (logB A) = 1.  So let's look at this problem: (log2 7) (log7 4).  It doesn't quite fit the pattern yet so we need to change it.  Look at the last term (log7 4).  If we can change this to (log7 2) it will fit the pattern.  So think of this as being (log7 2^2).  Using properties of logs (dealing with exponents) this is simply 2 * (log7 2).  So substituting we get : (log2 7) * 2 * (log7 2) or 2 * [(log2 7) (log7 2)] or 2 * 1 = 2.

I hope this answered all of your questions.  Write back soon if you have any more questions. 

Webmaster (Dewayne Jones)