30 (number) facts for kids

Thirty is a whole number that comes right after 29 and just before 31. It's an even number, which means you can divide it by 2 without anything left over. Thirty is also a composite number, because it has more than two factors (numbers that divide into it evenly).

You can find the number 30 in many places in our daily lives, from counting days in a month to sports scores and important age milestones.

What Makes Thirty Special?

Thirty is a fascinating number with several interesting mathematical features. It's the smallest number that can be divided by the first three prime numbers (2, 3, and 5) without any remainder. This makes it quite unique!

Factors of Thirty

When we talk about factors, we mean the numbers that divide into 30 perfectly. The factors of 30 are:

• 1
• 2
• 3
• 5
• 6
• 10
• 15
• 30

If you multiply any two of these numbers (like 2 and 15, or 3 and 10), you will get 30.

Multiples of Thirty

A multiple of 30 is any number you get when you multiply 30 by another whole number. For example, 60 (30 x 2) and 90 (30 x 3) are multiples of 30.

Thirty in Roman Numerals

In Roman numerals, which were used by the ancient Romans, the number 30 is written as XXX. Each 'X' stands for 10, so three 'X's together make 30.

Thirty in Everyday Life

The number 30 appears in many different areas, showing its importance beyond just mathematics.

Time and Calendars

Many months in our calendar have 30 days. For example, April, June, September, and November all have 30 days. This helps us keep track of time and plan our activities.

Sports and Games

In sports, 30 often marks important scores or time limits. For instance, in basketball, a shot clock might be set to 30 seconds. In tennis, "30" is a score during a game.

Age and Milestones

Turning 30 years old is often seen as a significant milestone in many cultures. It's a time when people might reflect on their lives and look forward to new beginnings.

Measurements

You might see 30 used in measurements, like a speed limit of 30 miles per hour or 30 kilometers per hour in some areas. It can also refer to 30 degrees on a thermometer or 30 centimeters for a length.

Images for kids

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  A friendly robot often used to represent kids' content.