Page 73 - Math Skill - 5

Fractions 71

1 1 5
5. A man travelled 57 km in a day. He covered 29 km by car, 21 km
2 3 6
by an autorickshaw and remaining on foot. How much distance did

he travel on foot?

4 7
6. What must be subtracted from 8 to get 3 10 ?
5
1 1
7. What must be added to 7 to get 11 ?
6 9
1
1
3
8. Which is greater: The difference between 1 and 3 or the sum of 1 3 and 1 ?
4 6 12 3
Multiplication of Fractions
Multiplication means repeated addition.
1 1
When we multiply a fraction, say by 4, we add four times.
3 3
1 ×= 1 + 1 + 1 + 1 = 4 = 1 1
4
3 3 3 3 3 3 3

Multiplying a Fraction by a Number
To multiply a fraction by a number, we use this formula.

Numerator of fraction × Number
Fraction × number =
Denominator of fraction

3 3 34 12 2
×
For example, let us multiply by 4 ×= = = 2
4
5 5 5 5 5
5 5 17 17 7× 119 5
Similarly, let us multiply 2 by 7 2 ×= ×= = = 19
7
7
6 6 6 6 6 6
Multiplying a fraction by another fraction

To multiply a fraction by another fraction, we use this formula.

Product of their numerators
Product of two fractions =
Product of their denominators

For example, let us multiply 3 and 4 = 3 × 4 = 34× = 12 = 6
10 11 10 11 10 11× 110 55

1 8
Similarly, multiply 7 by Absorbing Facts
8 15 “Discovery Vs Invention”
19 1 A discovery is recognizing something that already exists
1 8 57 8 19 4 but found for the first time. While, invention is something
7 × = × = = 3
8 15 8 15 5 5 that nobody has found before and create something new.
5 What do you think zero is an invention or discovery?