We know that, 1 m \(={1\over 1000}\) km
\(\therefore\)    8888 m \(=8888\times{1\over 1000}\) km
\(={8888\over1000}\) km = 8.888 km 

We have, \(0.60=\frac { 60 }{ 100 } =\frac { 60\div 20 }{ 100\div 20 } =\frac { 3 }{ 5 } \)
\(\left[ \because \quad HCF\quad of\quad 60\quad and\quad 100= 20 \right] \)

162 mm = 16.2 cm

\(\cfrac { 12 }{ 5 } =\cfrac { 12\times 2 }{ 5\times 2 } =\cfrac { 24 }{ 10 } =\cfrac { 20+4 }{ 10 } \)
=\(\cfrac { 20 }{ 10 } +\cfrac { 4 }{ 10 } =2+\cfrac { 4 }{ 10 } =2.4\)

Let us make a common place value table, assigning appropriate place value to the digits in the given numbers. We have,

Firstly, draw the number line and divide the unit length between two whole numbers into 10 equal parts, each of these equal parts represents 0.1 or 1/10. Now, locate the given decimals on this line.

(a) We have, 0.8
From the above figure, it is clear that number 0.8 lies between the whole numbers 0 and 1.
Hence, number 0.8 is nearer to number 1.
(b) We have, 5.1
From the above figure, it is clear that number 5.1 lies between the whole numbers 5 and 6.
Hence, number 5.1 is nearer to number 5.
(c) We have, 2.6
From the above figure, it is clear that number 2.6 lies between the whole numbers 2 and 3.
Hence, number 2.6 is nearer to number 3.
(d) We have, 6.4
From the above figure, it is clear that number 6.4 lies between the whole numbers 6 and 7.
Hence, number 6.4 is nearer to number 6.
(e) We have, 9.1
From the above figure, it is clear that number 9.1 lies between the whole numbers 9 and 10.
Hence, number 9.1 is nearer to number 9.
(f) We have, 4.9
From the above figure, it is clear that number 4.9 lies between the whole numbers 4 and 5.
Hence, number 4.9 is nearer to number 5.

Given, length of Ravi's pencil = 7 cm 5 mm
and length of Raju's pencil = 8 cm 3 mm
We know that, 10 mm = 1cm
\(\therefore\)1 mm = \(\frac { 1 }{ 10 } \) cm or one-tenth cm = 0.1 cm
Now, length of Ravi's pencil = 7 cm 5 mm
= 7 cm and 5 tenths cm
= 7cm + \(\frac { 5 }{ 10 } \) cm
= 7 crn+ 0.5 cm = 7.5 cm
and length of Raju's pencil = 8 cm 3 mm
= 8 cm and 3 tenths cm
=8 cm + \(\frac { 3 }{ 10 } \)cm=8 cm + 0.3 cm = 8.3 cm

Rs 634.50

To get the required number, we have
117.47 - 47.95 = 69.52

2.876 kg - 0.316 kg
i.e.   
\(\quad 2.876\\-0.316\\ \_\_\_\_\_\_\_\_\\ \ Rs\ 2.560 kg\\ \_\_\_\_\_\_\_\_\)

\(4.50=4+\frac { 50 }{ 100 } =4+\frac { 1 }{ 2 } =4\frac { 1 }{ 2 } =\frac { 9 }{ 2 } \)