NCERT Solutions for Class 7 Maths Chapter 2 Exercise 2.5
NCERT Solutions for Class 7 Maths Chapter 2 Exercise 2.5 (Ex. 2.5) Fractions and Decimals updated for academic session 2020-2021 free to use online or download. All the solutions are based on latest NCERT Books for 2020-2021 and following easy method during the solutions.In class 7 math exercise 2.5, we will learn how to convert a fraction into decimal and vice-versa. Comparison of decimal numbers and their addition and subtraction are the main focus in ex. 2.5 of class vii math.
Class 7 Maths Chapter 2 Exercise 2.5 Solution
|Chapter: 2||Fractions and Decimals|
|Exercise: 2.5||NCERT Textbook Solutions|
CBSE NCERT Class 7 Maths Chapter 2 Exercise 2.5 Solution in Hindi and English Medium
Class 7 Maths Chapter 2 Exercise 2.5 Solution in Videos
The numbers expressed in decimal forms are called decimals. A decimal has two parts namely
(i) whole-number part
(ii) decimal part
(i) Each of the number 6.8, 16.73, 7.364, 0.053, etc., is a decimal number.
These parts are separated by a dot (.), called the decimal point. The part on the left side of the decimal point is the whole-number part and that on its right side is the decimal part.
(ii) In 73.62 we have, whole-number part = 73 and decimal part = .62.
The number of digits contained in the decimal part of a decimal gives the number of decimal places.
5.74 has two decimal places and 8.536 has three decimal places.
Decimals having different number of decimal places are called unlike decimals.
Example: Clearly, 5.3, 8.64, 10.023 are unlike decimals.
An Important Result:
Putting any number of zeros to the extreme right of the decimal part of decimals does not change its value.
Thus, 3.8 = 3.80 = 3.800, etc., 2.94 = 2.940 = 2.9400, etc.
Arrange the digits of 374.568 in the place-value chart.
We may arrange the digits of the given number in the place-value chart as shown:
Hundreds – 3
Tens – 7
Ones – 4
Decimal point – .
Tenths – 5
Hundredths – 6
Thousandths – 8
Suppose we have to compare two given decimals. We follow the following steps to do this.
Step 1. Convert the given decimals into like decimals.
Step 2. First compare the whole-number part.
The decimal with the bigger whole-number part is greater.
Step 3. If the whole-number parts are equal, compare the tenths digits. The decimal with the bigger digit in the tenths place is greater.
Step 4. If the tenths digits are also equal, compare the hundredths digits, and so on.
Write the following decimals in ascending order: 5.74, 6.03, 0.8, 0.658 and 7.2.
Converting the given decimals into like decimals,
we get them as: 5.740, 6.030, 0.800, 0.658 and 7.200.
Clearly, 0.658 < 0.800 < 5.740. < 6.030 < 7.200. Hence, the given decimals in ascending order are: 0.658, 0.8, 5.74, 6.03, 7.2
In Mathematics, a decimal number can be defined as a number whose whole number part and the fractional part is separated by a decimal point. The dot in a decimal number is called a decimal point. The digits following the decimal point show a value smaller than one.
What are the 3 types of decimal numbers?
There are three types of decimal numbers:
(i) Terminating decimals: these have a finite number of digits after the decimal point.
(ii) Recurring decimals: these have one or more repeating numbers or sequences of numbers after the decimal point, which continue infinitely.
(iii) Decimals which go on forever, never ending and never forming a repeating pattern. These numbers are called irrational numbers and cannot be expressed as a fraction.
What are the four rules of decimals?
You should become efficient in using the four basic operations involving decimals—addition, subtraction, multiplication and division.