Page 134 - Start Up Mathematics_6

Example 6: Pankhuri has to dye 40 dresses. She has so far finished 30 dresses. What fraction of
dresses is still left?

Solution: Number of dresses to be dyed = 40
Number of dresses already dyed = 30
Number of dresses still left to be dyed = 40 – 30 = 10
10 1
∴ Fraction of dresses left = =
40 4
Example 7: Write the natural numbers from 1 to 11. What fraction of them are prime numbers?
Solution: Natural numbers from 1 to 11 are 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11.

Prime numbers from 1 to 11 are 2, 3, 5, 7, 11.
Total number of natural numbers from 1 to 11 = 11
Total number of prime numbers from 1 to 11 = 5
5
∴ The required fraction of prime numbers =
11
Example 8: Arushi received a Wii on her birthday. She got 5 CDs of games along with it and
received 8 others as gifts. What fraction of total CDs did she got with the Wii and
what fraction did she receive as gifts?
Solution: Number of CDs she got with the Wii = 5

Number of CDs she received as gifts = 8
Total no. of CDs = 5 + 8 = 13
5
Fraction of total CDs she got with Wii =
13
8
Fraction of total CDs she received as gifts =
13
Representation of Fractions on a Number Line

Fractions like whole numbers can also be represented on a number line.
1 1
To represent on a number line, we need to recall that lies midway between 0 and 1.
2 2

0 1 1
2
1
Similarly, we can show on a number line as it trisects the segment between 0 and 1 and is nearer
to 0 as shown below: 3

0 1 1
3
3
Example 9: Show on a number line.
4
Solution: We first divide the line segment between 0 and 1 into four equal parts. The third
3
mark from the origin represents .
4

0 3 1
4
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