The Number Quiz: Do You Know Everything About The Number 21?

1) What is the roman numeral for 21?

XIIII

XXIIII

XXI

XX

The correct answer is XXI. In Roman numerals, X represents 10 and I represents 1. So, XX represents 20 and adding I to it gives us 21.

Explanation

The correct answer is XXI. In Roman numerals, X represents 10 and I represents 1. So, XX represents 20 and adding I to it gives us 21.

2) What are you permitted to do once you turn 21?

Smoke.

Get a job.

Drink alcohol.

Drive a car.

Once you turn 21, you are legally allowed to drink alcohol. In many countries, the legal drinking age is 21, and reaching this age grants individuals the permission to consume alcoholic beverages. This is a significant milestone for young adults as they are now able to legally participate in social activities involving alcohol and make responsible choices regarding its consumption.

Explanation

Once you turn 21, you are legally allowed to drink alcohol. In many countries, the legal drinking age is 21, and reaching this age grants individuals the permission to consume alcoholic beverages. This is a significant milestone for young adults as they are now able to legally participate in social activities involving alcohol and make responsible choices regarding its consumption.

3) Name all of the factors of 21.

1,21

1,3,21

1,3,7,21

1,3,4,7,21

The factors of a number are the numbers that can divide it evenly without leaving a remainder. In this case, the factors of 21 are 1, 3, 7, and 21. These numbers can all divide 21 without leaving any remainder. Therefore, they are all factors of 21.

Explanation

The factors of a number are the numbers that can divide it evenly without leaving a remainder. In this case, the factors of 21 are 1, 3, 7, and 21. These numbers can all divide 21 without leaving any remainder. Therefore, they are all factors of 21.

4) is won by the first player to get 21 points.

Tennis

Basketball

Table tennis

Lacrosse

Table tennis is won by the first player to get 21 points. This means that in a game of table tennis, the player who reaches 21 points first wins the game. This scoring system adds a level of excitement and suspense to the game, as players must strategize and compete to reach the winning score before their opponent does.

Explanation

Table tennis is won by the first player to get 21 points. This means that in a game of table tennis, the player who reaches 21 points first wins the game. This scoring system adds a level of excitement and suspense to the game, as players must strategize and compete to reach the winning score before their opponent does.

5) What element is number 21 on the periodic scale?

Gallium

Scandium

Strontium

Sulfur

Scandium is the element number 21 on the periodic scale. It is a transition metal with the symbol Sc and atomic number 21. Scandium is a silvery-white metal that is relatively soft and has a high melting point. It is commonly used in the aerospace industry due to its lightweight and high strength properties. Scandium is also used in the production of high-intensity lamps and as an additive in some alloys to improve their performance.

Explanation

Scandium is the element number 21 on the periodic scale. It is a transition metal with the symbol Sc and atomic number 21. Scandium is a silvery-white metal that is relatively soft and has a high melting point. It is commonly used in the aerospace industry due to its lightweight and high strength properties. Scandium is also used in the production of high-intensity lamps and as an additive in some alloys to improve their performance.

6) Which group does 21 not fit into?

Harshad

Triangular

Composite

Prime

The number 21 does not fit into the group of prime numbers because it is divisible by numbers other than 1 and itself. In this case, 21 can be divided evenly by 3 and 7. Prime numbers are only divisible by 1 and themselves, so 21 does not meet this criteria.

Explanation

The number 21 does not fit into the group of prime numbers because it is divisible by numbers other than 1 and itself. In this case, 21 can be divided evenly by 3 and 7. Prime numbers are only divisible by 1 and themselves, so 21 does not meet this criteria.