DECIMAL FRACTIONS
Solved exercise of decimal fraction
Summary
Decimal fraction is a fraction whose denominator is 10 or a multiple of 10 like 100, 1,000, 10,000, etc.
Decimals can also be used to write numbers between any two whole numbers.
Example
While measuring the length of a table with a metre scale, the length may not be a whole number, it may lie between two graduations on the metre scale. In such situations, the decimal numbers are used.
From the conservation of units we know
1 km = 1000 m
1 m = 100 cm
1 cm = 10 mm
Now, let the length of the tabletop be 2 m and 75 cm, and then it can be represented as
(2 + 75/100) m.
Exercise
Exercise 4.1
Read the following decimals and write them in words
1) 0.5 = zero point five
2)0.13 = zero point one three
3)1.7 = one point seven
4)5.21 = five point two one
II. Write the numeral representing each of the following
1) Zero point one-two = 0.12
2) Six point eight = 6.8
3) Ten point five =10.5
4) Four point zero two =4.02
5) Six point eight four =6.84
6) One hundred eight point zero six =108.06
III. Fill in the blanks.
1)8 mm = 0.8 cm
1cm= 10mm
8mm=8/10= 0.8cm
2)75mm=7.5 cm
1cm = 10mm
75mm= 75/10=7.5cm
3)8cm 5mm=8.5 cm
1cm=10mm
5mm=5/10=0.5
8+ 0.5 =8.5 cm
4) 525mm=5.2 cm
1mm =10/10
525mm = 525/10 =52.5cm
IV. Fill in the blanks.
- 8 cm =0.08m
- 72 cm = 0.72m
- 375 cm = 3.75m
- 4m 80 cm =4.08m
- 15 m 6 cm =15.06m
V. Write in decimal fractions
1) 75 paise =Rs 0.75
2) 10 rupees and 25 paise =Rs10.25
3) 870 paise =8.70
4) 782 rupees and ten paise =Rs 782.10
5) 2050 paise = Rs 20.50
Example
To write the decimal fraction 1.42 in the form of fraction.
1) Write the number without decimal point that forms the numerator → 142
2) Count the decimal places in the decimal fraction i.e, 2
3) Write 1 followed by two zeroes in denominator → 100
I.Write the following fractions as decimal fractions.
1)8/10 =0.8
2)7/10 =0.7
3)6/10 =0.6
4)16/16 =1.6
5)83/10 = 8.3
6) 7/100 =0.07
7) 72/100 =0.72
8) 861/100 =8.61
9)162/10 =16.2
10) 141/100=1.41
11) 1461/100=14.61
12) ½ =0.5
13) ¾ =0.75
14)2/5 =0.4
15)7/20 =0.35
16)38/50 =0.76
17)17/25 =0.65
18)13/20 =0.65
19)8/25=0.32
II.Write the following decimal fractions as fractions
1)0.7
7
10
2) 0.02
2
100
3) 3.8
38
10
4)14.5
145
10
5)0.56
56
100
6)8.03
803
100
7)14.57
1457
100
8)85.4
854
10
9)147.5
1475
10
10)8.5
85
10
11)85.61
8561
100
12)6.84
684
100
