Page 9 - TP_Pluse_V2.2_Class_7
P. 9
1 Number System
Let’s surf
Ø What is a Number System? Ø Decimal to Binary Conversion
Ø Binary to Decimal Conversion Ø Operations on Binary Numbers
21 st
Let’s PLug-in Century #Critical Thinking
Skills
Solve the following sums. Also note the time you took to solve each of them.
1. 345678 – 789 = _______ (Time taken to solve: _______)
2. 567 x 55 = _______ (Time taken to solve: _______)
3. 100 x 9 + 890 – 67 = _______ (Time taken to solve: _______)
4. 22/11 + 20 – 4 x 2 = _______ (Time taken to solve: _______)
Do you know how computer solves these sums and how quickly it does it? Let's find out in this chapter.
A computer takes data from a user and produces result as information. Although the words data
and information are often used interchangeably, but there is an important distinction between the
two words. In the strict sense, data consists of the raw numbers that computers organise to produce
information.
From an early age, we are introduced to the concept of numbers and counting. Toddlers learn at an
early age that they can carry two cookies, one in each hand. Kindergarteners start counting by twos
and fives. Invariably, we use the decimal number system. Our number system is based on 10, most
likely because we have 10 fingers. Let us learn more about the number system.
Tech Fact
The numerical digits, we use today, i.e., 1, 2 and 3 are based on the Hindu-Arabic
numeral system.
Different names for the number 0 include zero, nought, naught, nil, zilch and zip.
Number System 7

