Page 87 - Maths Class 05

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We have used Repeated Addition. We could also multiply 10 by .
2
Alternative Method : 1
10 × = ?
2

Solution : To multiply a whole number and a fraction.

10
Step 1 : Write the whole number as a fraction =
1

Step 2 : Multiply the numerators 10 × 1 = 10

Step 3 : Multiply the denominators 1 × 2 = 2

10
Step 4 : Simplify to the lowest term = 5
2
So, Simran made 5 burgers.

Multiplication of Mixed Numbers by Whole Numbers

Example : 3 1 × 8 = ?
4

1 13 13 8 13 × 8 13 × 2
Solution : 3 × 8 = × 8 = × = = = 26
4 4 4 1 4 × 1 1

Know
Know
Know
Get
Get
Get to
to
Product of their numerators
Product of two fractions =
Product of their denominators

Multiplication of Fractions by a Fraction

1 2
Example : Let us multiply and .
6 3
1 2
Solution : × = ?
6 3
1 2
Product of numerators of and = 1 × 2 = 2
6 3
1 2
Product of denominators of and = 6 × 3 = 18
6 3

1 2 2 1
Product of and = =
6 3 18 9
1
As is already in the lowest term, so we don’t need to simplify.
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Mathematics-5 87