Page 189 - New Medley 5 Semester 1

Z Z Multiplicative inverse of a proper fraction is an improper fraction and
vice-versa.

Z Z Multiplicative inverse of a whole number is a unit fraction and vice-
versa.

Division of Fractions

Dividing a Whole Number by a Fraction

1
Consider the division 4 ÷ (i.e., the number of one-thirds in 4).
3

We take four triangles to represent 4 wholes and divide each of them into

3 equal parts. How many parts are there in all?

3 parts + 3 parts + 3 parts + 3 parts = 12 parts in all

3 12
Also, 4 × = = 12
1 1
1 3
Thus, 4 ÷ = 4 × = 12
3 1

1
In the same way, the number of quarters in 5, i.e., 5 ÷
4

4 quarters + 4 quarters + 4 quarters + 4 quarters + 4 quarters = 20 quarters

1 4 20
So, the number of quarters in 5 = 5 ÷ = 5 × = = 20

4 1 1
Hence, we observe that dividing a whole number by a fraction is the

same as multiplying the whole number by a reciprocal of the fraction.

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