Question

How many symbols are used in Roman Numerals?
A. 7
B. 6
C. 9
D. 12

Answer 1

Hint: Here, what are roman numbers and how to use it in appropriate ways should be known. Also, which letter indicates what number should also be known otherwise the meaning of the numerals can be changed. We will see letters used in this counting system.

Complete step by step solution:
Roman Numerals as this name suggests, have originated from ancient Rome. Since that time they used some of the letters to indicate numbers instead of using 0-9 numbers. These letters were used for communications as well as in trading as counting through fingers was becoming very tedious in those days. So, they invented a unique system for counting with the help of some letters.
Letters used in that counting system are: I, V, X, L, C, D, and M. All these alphabets have their own meaning.
Here, I stand for one finger or one unit.
V stands for five fingers or we can say only number 5.
X is equal to number 10.
L is equal to number 50.
C is equal to number 100.
D is equal to number 500.
M is highest i.e. number 1000.
Let us discuss how these numerals work. For example, we take number 13; this is represented in roman numerals as XIII. Means X for 10 plus I for 1 three times, so $10+1+1+1=13$.
Thus, 7 symbols are there in Roman Numerals.
Option (a), is the correct answer.

Note: All these alphabets can be repeated only 3 times, not more than that. Be careful while denoting any numbers because there are some set of rules regarding these symbols how to use in addition or subtracting two numbers. Like if \[{{1}^{st}}\] symbol appears larger than \[{{2}^{nd}}\] one then it should be added, for example: VII $=5+1+1=7$. And, if \[{{1}^{st}}\] symbol is smaller than \[{{2}^{nd}}\] one then it means subtraction, for example: IX $=\text{X}-\text{I}=10-1=9$ .