This week let us look at logical thinking and reasoning. What is logical reasoning? It involves one's ability to identify and solve any given problem. A person with greater logical reasoning ability is better equipped to work in positions that require quick decision-making. That is why logical reasoning questions commonly appear inmany competitive or entrance examinations.
To start with let us take a simple problem that requires logical reasoning. You send a valuable object in a box to a friend in the neighbouring town. Asit is valuable you need to lock the box. The box has a ring that is more than large enough to attach a lock to. Both you and your friend have several locks with keys. But the problem is that your friend does not have the key to any lock that you have, and vice versa. From the safety aspect you cannot sendthe key to him. How will you solve the problem?
(I will give you a tip. The person who is to take the box can travel to and fro between the towns many times a day).
The answer: You put the valuable item in the box, lock the box and send it. When your friend receives the box he adds another lock and sends it back to you. You remove your lock and send the box back to him. Now he can open his lock and open the box.
Vedic math is a tool that can be used to crack many logical reasoning questions and quantitative aptitude questions in competitive exams.
To move further on our learning path in vedic math, it is important that we recollect methods that we have already studied.
Let us recollect squaring of numbers ending in 5. For this we multiply the first part by the next higher number.
Example: Find the square of 65
6 5
6 x 7 52
42 25
First we separate 65 into two parts: 6 and 5
Multiply 6 (the first part) by the next higher number.
6 + 1 = 7. 6 x 7 = 42
Next square the second part 52 = 25
Put the two parts together and you get your answer
Answer: 4225
Next we recollect the method to multiply numbers with 2 or more digits
by 11. This method involves not multiplication but addition of neighbouring
digits.
Example: 43 x 11
Write down the given digits and place the sum of the digits between
them
4 (4 + 3 = 7) 3
The answer is 473
Let us see another sum: 79 x 11
7 16(7 + 9) 9
Since 16 has two digits the first is carried over: 8 6 9
Answer: 869
Practise these and apply them in your math problems.
Tip of this week: Think before you answer.