In the first article I talked about how important it is to master mental mathematics so that this can help you through both school and in life situations.
In this article I help you to take the first step of mental mathematical knowledge, which is to memorize the addition of single-digit numbers – being the numbers 0-9. When two of these single-digit numbers are added the value is a number in the range 0-18.
In this age of the calculator, why should you have to learn to do arithmetic in your head?
Surely the reason that we have the calculator is to help us do our calculations, and it is a tool for all of mankind, including school children, just like the motor car is a tool to get us from one place to another to save on walking.
When confronted with mathematical problems I always recommend that you should use the APEX method which I propose.
This APEX method provides a simple and effective way to deal with any mathematical problem, no matter how small or large, and no matter how apparently easy or hard.
Let us see what we have and what we are supposed to give as the answer.
We are told that there are three boxes, labelled GOLD, SILVER, and LEAD.
We are also told that there is a painting inside one and only one of these boxes.
We are further told that there are some statements written on the boxes:
We are also told that two of the statements are FALSE, and that one is TRUE.
It is clear that this is a logical problem, since problems which involve finding TRUE and FALSE are mostly logical in nature.
One approach is to see which can be TRUE and which can be FALSE, and this means that each of the statements can be either TRUE or FALSE, thus there are 2 choices for each box, and thus there 2x2x2 possibilities, since there are three boxes in total, and this makes 8 total choices.
Firstly, since there are two FALSEs and only one TRUE, then the number of choices is actually only three. The TRUE is either GOLD, SILVER, or LEAD, with the other two being FALSE.
Secondly, it is also clear that the statements on the GOLD and LEAD boxes are in conflict, since they cannot both be TRUE. This means that the TRUE and one of the FALSEs is already allocated, and thus the SILVER can only be FALSE.
If SILVER is FALSE then ths statement that the painting is NOT in the SILVER box is FALSE, and thus the painting IS in the SILVER box.
However, we have not yet allocated the TRUE and FALSE to the GOLD and SILVER boxes, so could the painting be in one of these as well? Let us crosscheck to see.
Firstly let us consider that the GOLD box is FALSE, and the LEAD box is TRUE.
Now let us consider that the GOLD box is TRUE and the LEAD box is FALSE.
Thus the answer is that the GOLD box is FALSE, the SILVER box is FALSE, and the LEAD box is TRUE, and the painting is in the SILVER box.
There are a number of interesting funny videos available which illustrate specific points, and most of these are based upon completely wrong mathematics which someone is trying to convince someone of:
Look at these two…
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This is the finalpart of the solution for the problem which I provided a few days ago. If you have not read this then please start from the first part of this problem – When is Cheryl’s birthday.
Yesterday I provided the second hint to you, and we concluded with the following:
blockquote>STATEMENT 3: Bernard: At first I don’t know when Cheryl’s birthday is, but I know now.
Bernard is able to tell which is the correct date simple from what Albert said in STATEMENT 1. So how could he deduce this?
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