This Post Has 13 Comments

  1. The problem sets often test your ability to translate funny wording into equations and then use logic to solve. How comfortable are you understanding the different worded questions in Problem Set #1?

    1. If the question were (103 x 1000) times (102 x 100) times (101 x 10) then that would equal
      (106 x 104 x 102) = 10(6 + 4 + 2) = 1012
      BUT the question is (103 x 1000) plus (102 x 100) plus (101 x 10) and that equals (106 + 104 + 102)

      The question is designed to trap students who know that you can add the exponents when multiplying exponential terms with the same base. It assumes most kids taking the exam know this so well it will be a routine calculation. So routine, in fact, many students will rush through it and make the mistake of answering 1012. The question is really testing your ability to read the question carefully! Remember, read questions very carefully on the exam or you will make mistakes on material that you know.

  3. For number 14 in Practice Drills- Converting Decimals-Fractions-Pct can you plz explain how you got the answer for number 14. It is the one about how a race horse goes 6:5 odds and if i bet $5 dollars on a horse to win at 2:5 odds and it wins then what is the value of my winning ticket. Please explain…

    1. If 6:5 odds pay a $6 profit for every $5 bet then the ratio 6:5 represents $ profit:$ ticket.
      As a result, 2:5 is $2 profit : $5 ticket. A $5 bet will result in a $2 profit if the bet pays off at the stated odds. In other words, a $5 winning ticket becomes worth $5 original bet plus $2 profit which equals $5 + $2 = $7 ticket value.
      Recall, ratios are expressed part:part which is a little different than fractions which are expressed part/total. Those parts can and will be defined in the problem as they are in this case so pay close attention to the wording of the ratio problem. The total ticket value in this case is part1 + part2 = original ticket value + profit value = total value.
      Let me know if you still have any questions or if this isn’t clear for any reason.

  4. Not sure if this is the right spot to post, I did email customer_service but didn’t get a reply.

    Here is my question – After completing the lesson 2 testprepshsat, I’m getting this (pasted below). What does this mean?
    *The Factors module will advance to the beginning again if you do not Return to ‘Tips and Drills’ at this point.**

    1. An average calculation between two values can be performed. The midpoint formula applies an average calculation to both both coordinates, x and y. This problem is not a coordinate pair, however.

  6. Also, for number 20 on Problem Set 01, the question had asked for how many different whole number factors are there. So, how come the solution was just to find how many factors? Wouldn’t we have to solve it on the basis so 2 wouldn’t be repeating since it asks for the different whole number factors and not the factors in general?

    1. Factors of any positive integer are whole numbers. Otherwise, there could be infinite factors to any given integer. The solution uses the prime factors to count the number of (whole number) factors.

  7. How do you solve the questions:

    “A chemist claims that he has found a chemical formula that will kill a certain bacteria. He claims it will kill half the bacteria in 40 seconds, and in the next 40 seconds kill half of the remaining half, and so on. If he is correct, and at a certain time there are 30 bacteria still alive, how many bacteria were alive 4 minutes earlier?”

    The 21st century will begin on 1 January 2001. What day of the week will that be?

    Sound travels at about 330 meters per second, but light travels so much faster that it travels almost instantaneously. How long a gap do you expect between seeing the flash and hearing the thunder from a storm 4km away?

    thank youu!!

    1. If half a re killed every 40 seconds then every 40 seconds back in time, the amount doubles. There are 6 40 second periods in 4 minutes, so the answer is 30 x 2^6 = 30 x 64 = 1920.

      How many days away is that from a known date and day of the week? A week is always 7 days without exception. This is a multiple and remainder problem.

      You see the light at the moment of the strike. You will hear the thunder (produced by the lightning) 4000M/330M or about 12 seconds later.

Leave a Reply

This site uses Akismet to reduce spam. Learn how your comment data is processed.

Back To Top