Question

Convert the given Roman Numerals ‘XC’ and ‘C’ in English numerals and then find its difference.
A. 100
B. 20
C. 10
D. 12

Answer 1

Hint: In such a type of question, firstly we have to know the meaning of the Roman Numerals ‘XC’ and ‘C’. After this, convert the Roman numerals into English numerals. To find out the difference between them subtract one number from another number.

Complete step-by-step solution:
Firstly let us understand the Roman Numerals. In Roman Numerals generally I, V, X, L, C, D, and M are used.
Let us see the below table for converting these Roman numerals into English Numerals.

Sr. No	Roman Numerals	English Numerals
1	I	One (1)
2	V	Five (5)
3	X	Ten (10)
4	L	Fifty (50)
5	C	Hundred (100)
6	D	Five Hundred (500)
7	M	Thousand (1000)

In Roman Numerals for some specific cases to avoid four characters being repeated in succession (like IIII or XXXX) subtractive notation is often used.
Like if I is placed before X indicates one less than ten means nine. Also if X is placed before L means ten less than fifty means forty. Also if L is placed before D means fifty less than five hundred. Similarly if C is placed before D or M means hundred less than five hundred or hundred less than thousand.
So, here the given two roman numerals are ‘XC’ and ‘C’. We know that Roman numerals ‘C’ means Hundred. And for Roman numeral ‘XC’, X is placed before C means ten less than a hundred. So the meaning of ‘XC’ is ninety.
So, $XC=90$ and $C=100$.
Difference between these two Roman numerals is given by $100-90=10$.
So, the difference between ‘XC’ and ‘C’ Roman numerals is 10.

So, Option (C) is the correct answer.

Note: In Roman Numerals for some specific case addition notation is often used. Like if I is placed after V means one more than 5 means six. Like X is placed after L means ten more than fifty means sixty. Likewise L placed after D means fifty more than five hundred.