summary of chapter 2 Fractions and decimal class 7 or introduction
Answers
Answer:
This is your answer ↓↓↓
Introduction: Fractions
The word fraction derives from the Latin word “Fractus” meaning broken. It represents a part of a whole, consisting of a number of equal parts out of a whole.
E.g : slices of a pizza
Representation of Fractions
A fraction is represented by 2 numbers on top of each other, separated by a line. The number on top is the numerator and the number below is the denominator. Example :34 which basically means 3 parts out of 4 equal divisions.
Fractions on the Number Line
In order to represent a fraction on a number line, we divide the line segment between two whole numbers into n equal parts, where n is the denominator.
Example: To represent 1/5 or 3/5, we divide the line between 0 and 1 in 5 equal parts. Then the numerator gives the number of divisions to mark.
Division of Fractions
Reciprocal of a Fraction
Reciprocal of any number n is written as1n
Reciprocal of a fraction is obtained by interchanging the numerator and denominator.
Example: Reciprocal of 2/5 is 5/2
Although zero divided by any number means zero itself, we cannot find reciprocals for them, as a number divided by 0 is undefined.
Example : Reciprocal of 0/7 ≠ 7/0
Multiplication of Decimals
Multiplication of decimal numbers with whole numbers :
Multiply them as whole numbers. The product will contain the same number of digits after the decimal point as that of the decimal number.
E.g : 11.3×4 = 45.2
Multiplication of decimals with powers of 10 :
If a decimal is multiplied by a power of 10, then the decimal point shifts to the right by the number of zeros in its power.
E.g : 45.678×10 = 456.78 (decimal point shifts by 1 place to the right) or, 45.678×1000 = 45678 (decimal point shifts by 3 places to the right)
Multiplication of decimals with decimals :
Multiply the decimal numbers without decimal points and then give decimal point in the answer as many places same as the total number of places right to the decimal points in both numbers.
Hope it helps !!!
Please Mark me the brainliest !!!
Answer:
Introduction to Fractions
We have already learnt how to compare to fractions and also how to add and subtract fractions. In proper fraction, the denominator is bigger than numerator. For example, 3/4 is a proper fraction. A fraction like 11/5 is an example of an improper fraction. In an improper fraction, the numerator is bigger than the denominator and it has two parts, the whole number part and fractional part.
11/5 = 2 1/5, which is in the form of a mixed fraction.
Fractions having the same denominators are called like fractions. Example,3/11,7/11,8/11 and so on. Fractions with different denominator are called unlike fractions. Example,2/7,1/5,1/4 and so on.
Introduction to Decimals
Write the expanded form of decimal.
1) 4235.175
Solution:- 4000 + 200 + 30 + 5 + 5/10 + 9/100.
1) 4235.175
Solution:- 4000 + 200 + 30 + 5 + 0.1 + 0.07 + 0.005
2) 5.607
Solution:- 5×1 + 6/10 + 0/100 + 7/1000
= 5 + 0.6 + 0.00 + 0.007
