Answer: Option C. -> Whole Numbers
:
C
Whole numbers are the numbers starting from 0 and including all the natural numbers.

:
Each part: 1 Mark
a) XXX.
Now, we now that if a symbol is repeated, its value is added asmany times as it occurs.
XXX = 10 + 10 + 10 = 30.
b) IX
I=1
X=10
1<10
If a smaller value is written to the left of a symbol of greater value, its value is subtracted from the value of the greater symbol.
$\therefore$ The value IX = 10 - 1 = 9.
c) VII
If a symbol of smaller value is written to the right of a symbol of greater value, its value gets added to the value of the greater symbol.
V=5
I=1
$\therefore$ The value of VII = 5 + 1 + 1 = 7.
d) XII
In this case, also, the smaller value is written to the right of the greater number. So its value is added to the value of the greater symbol.
XII= 10 + 1 + 1 = 12.

:
Concept: 1 Mark
Steps: 2Marks
Answer: 1 Mark
We know that ,1 km = 1000 m
Now total distance walked by Anshul = 5.5 (house to office) +2 km (way back from office)
Now 1 km = 1000m
$\therefore$ 5.5 km = 5.5 $\times$ 1000 = 5500 m
2 km = 2$\times$1000 = 2000 m
Now total distance walked by Anshul = 5.5 + 2 km = 5500 + 2000 = 7500 m

Answer: Option A. -> 84942
:
A
The largest number formed by using the given digits is 97421 and the smallest digit number formed is 12479. So the difference between them can be calculated as,
97421 - 12479 =84942.

Answer: Option C. -> 5400
:
C
5873 - 436 = 5437
5437 is less than 5450,the mid point of 5400 and 5500.
Hence, 5437 rounded off to the nearest hundreds is 5400.

Answer: Option B. -> False
:
B
1 Lakh = 100000
1 Thousand = 1000
$\therefore 1Lakh=HundredThousand$

:
Using the digits 6, 3 and 8 the smallest number that can be formed is 368 and the largest will be863.

:
Money Spent = 375 + 155 + 285 = 815
Money left = 1000 - 815 = 185
When it is rounded off to nearest hundred it will be Rs 200

:
In 98429758 place value of 2 is 20000 and place value of 7 is 700. So the difference between them will be 19300.

Answer: Option B. -> I:L
:
B
The time shown on the clock is 01:50. 01 in Roman numeral form is I. 50 in Roman numeral form is L.
So 01:50 will be represented as I:L