Lesson 2: Reinforcing Step by Step Thinking and Logical Reasoning

Lesson 2: Reinforcing Step by Step thinking and logical Reasoning

AIM

In this lesson you will learn:

Activities are done following some specific steps

How logical reasoning can help you to optimise the effort to complete any activity

Consider any day to day activity, like buying grocery from the shop. Before actually going and buying the item, we have to follow a series of steps. Let us now consider the steps we have to follow:

a. Prepare a list of items to be bought.

b. Go to the shop.

c. Select the items needed.

d. Pay the money.

e. Take the things home.

In this sequence we have to follow the steps in same order. For example, without preparing the list if we reach the shop, we may miss some of the items needed. Similarly, without selecting the items you can't pay the money.

Now let us see another example:

Your mother wants to do two things. a. Pick you up from the school

b. Buy some groceries.

Now your mother can either pick you up first and then go to the grocery store or buy things from the grocery store and then come to school to pick you up. Either way it is fine.

Now how does she decide what to do first?

This is where she has to think and answer questions like what happens if I buy the grocery first?, why should I go to the school first?, etc.

For answering these questions we have to consider different options, like the time in our hands. If your mother is leaving the house, just minutes before your school leaves, she will first pick you up and then go to the grocery store. Now if she has enough time, then she can do the grocery shopping first.

Another option to consider is the distance to be travelled. If the grocery store is on the way to the school, then she can do the shopping and come to the school. Here also we have to see the time. So for doing any activity we have to consider different factors.

Now let us see another example. Tejas wants to go to Jyoti's house. If more than one path is available, which one will he choose?

The following figure gives you the location of Tejas's and Jyoti's house. He can take any path he wants according to his convenience.

If he takes path one he can pay a visit to Neha's house as well before going to Jyoti's house. In path two, Tejas can make a visit to the school library before going to Jyoti's house. Path three will take Tejas straight to Jyoti's house.

To decide upon the path, which he will take, he has to consider time, if he has enough time he can choose path one. But if Neha is out of town, Tejas will not take path one. If Tejas don't have enough time to spend in the school library, he will take path three which takes him straight to Jyoti's house.

Thus we see that for each and every activity can be divided in simpler tasks or steps. In some activities the order of the steps can be changed while in some others it may not be changed. Even after we decide upon the sequence of steps other factors like time, the necessity, etc need to be considered.

Work Sheets

1. A drawer contains 10 black and 10 brown socks that are all mixed up. What is the fewest number of socks you can take from the drawer without looking and be sure to get a pair of the same color?

1. Moz has asked Jyoti and Tejas a puzzle: “Two fathers and two sons went fishing. Each caught exactly one fish and yet there were only three fish caught. Why?” Can you help them in solving this.(Icon of Jyoti and Tejas)

1. Here is a sequence of colours. Guess what colour comes in the next two spaces?

1. Sudoku Puzzles

 Observe the following table. You can use only the numbers from 1 to 4. All the rows and columns should have these numbers(1, 2, 3, 4) and only once. Fill in the missing numbers.

 Observe the following table. All the rows and columns need to filled in with the shapes: Circle, Diamond, Square and Rectangle. All the rows and columns should have these shapes. Now complete the puzzle.

1. Make the following numbers with the numbers 1, 3 , 7, 9. You can use the operations addition, subtraction, multiplication and division.

Example: 0 = 7 + 3 – 1 – 9

 1 =

 2 =

 3 =

 4 =

 5 =