Ordinal Numbers

Grade 1 · Math · Study Guide

Learn how to use ordinal numbers to describe position in order, like first, second, and third.

Ordinal numbers tell us the position or order of things, not just how many. Instead of saying 1, 2, 3, we say first (1st), second (2nd), third (3rd), and so on. We use ordinal numbers all the time — like when we talk about who finished a race first or which floor of a building we are on.

The first five ordinal numbers are a little special: first, second, third, fourth, fifth. After that, the pattern becomes easier — sixth, seventh, eighth, ninth, tenth. Notice they all end in 'th' from fourth onward, though first, second, and third are unique.

When we write ordinal numbers with numerals, we add a suffix: 1st, 2nd, 3rd, 4th, 5th. These are useful on calendars, in races, and whenever we put things in a line or sequence!

Key terms

ordinal number

A number that shows the position or order of something (first, second, third...)

position

Where something is in a sequence or line

1st

First — the one at the very beginning or front

2nd

Second — right after first

3rd

Third — right after second

Flashcards

1st

First — comes at the very beginning

2nd

Second — comes right after first

3rd

Third — comes right after second

5th

Fifth — the position of the 5th item in a line

Ordinal Number

A number that tells position or order (1st, 2nd, 3rd...)

10th

Tenth — the position of the 10th item in a line

Practice questions

1. In a race, Maya finished right after the person in first place. What place did Maya finish?

   1. First
   2. Third
   3. Second
   4. Fourth
   Show answer

   Answer: Second

   Second place (2nd) comes right after first place

2. The short form of fourth is 4th.

   Show answer

   Answer: True

   Fourth written as a numeral with suffix is 4th

3. The ordinal number for 7 is ___.

   Show answer

   Answer: seventh

   7 in ordinal form is seventh (7th)

4. A train has 6 cars. Which car is last?

   1. 5th
   2. 1st
   3. 6th
   4. 4th
   Show answer

   Answer: 6th

   The last car in a 6-car train is in the 6th position

5. Which is the correct short form for 'third'?

   1. 3nd
   2. 3th
   3. 3st
   4. 3rd
   Show answer

   Answer: 3rd

   Third is written as 3rd; the suffix for third is 'rd'

Fun facts

• The Olympics gives gold medals to 1st place, silver to 2nd, and bronze to 3rd — ordinal numbers in action!
• In many countries, apartment floors are counted with ordinal numbers — you might live on the 3rd floor!

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