Tenths in Math: Definition, Place Value & Examples

Definitionnoun

What are tenths in math?

Tenths are the parts you get when one whole is split into 10 equal parts; each part is one tenth, written 110 or 0.1. The tenths place is the first digit to the right of the decimal point, so in 4.7 the 7 means 7 tenths, or 0.7.

In Spanish: décimos
Also called: tenth, tenths place, one tenth, 0.1
Grade level: K-5

Grade 3Grade 4Grade 5CCSS 4.NF.C.6CCSS 5.NBT.A.1GEDTABE

Tenths in a picture

Seven tenths is 7 of 10 equal parts. It can be shaded in a bar, placed on a number line, or written as the first digit after the decimal point.

Formal definition and notation

One tenth is the fraction 110, the quantity formed by 1 part when a whole is partitioned into 10 equal parts. In base-ten notation, a digit d in the first place after the decimal point has value d × 110. The tenths place is 110 of the ones place to its left and 10 times the hundredths place to its right.

Symbol	Read it as	Meaning
110	one tenth	one of 10 equal parts of a whole
0.1	one tenth, or zero point one	the same number written as a decimal
0.7	seven tenths	710: 7 parts out of 10

Key facts

10 tenths make 1 whole, and 1 tenth is 10 hundredths: 0.1 = 0.10.
The tenths place is the first place to the right of the decimal point.
To compare decimals, compare the tenths digits first when the whole-number parts match: 0.4 is greater than 0.35 because 4 tenths beats 3 tenths.
Rounding to the nearest tenth keeps one digit after the point: 6.48 rounds to 6.5.
Dividing by 10 turns ones into tenths: 7 ÷ 10 = 0.7.

Tenths as fractions and decimals

0.d = d10

d: the digit in the tenths place, 0 to 9
10 tenths: make 1 whole: 1010 = 1

A number like 2.3 is 2 wholes and 3 tenths, which is 2310, or 23 tenths.

Try it: count by tenths

Interactive

Drag the point. It snaps to tenths, and the readout shows the same place as a fraction and a decimal. Try to land on 1.3, which is 13 tenths.

This interactive needs JavaScript. The worked examples below show the same ideas step by step.

Tenths examples, step by step

Example 1: Decimal to fraction

Warm-up

Write 0.6 as a fraction in simplest form.

0.6 is 6 tenths: 610.
Divide top and bottom by 2: 610 = 35.

Answer: 0.6 = 35.

Example 2: Adding tenths with regrouping

Core

Find 0.8 + 0.5.

8 tenths + 5 tenths = 13 tenths.
10 tenths make 1 whole, so 13 tenths = 1 whole and 3 tenths.

Answer: 0.8 + 0.5 = 1.3.

Example 3: Rounding to the nearest tenth

Test-style

A runner’s time is 12.46 seconds. Round it to the nearest tenth of a second.

The tenths digit is 4, so the choices are 12.4 and 12.5.
Look at the next digit (hundredths): 6 is 5 or more, so round up.
12.46 → 12.5.

Answer: The time rounds to 12.5 seconds.

Common mistakes

✗ MistakeSaying 0.35 is greater than 0.4 because 35 is greater than 4.

✓ InsteadCompare tenths first: 0.4 has 4 tenths and 0.35 has only 3 tenths, so 0.4 > 0.35.

Digits after the point are compared place by place. 0.4 = 0.40, which is 40 hundredths, more than 35 hundredths.

✗ MistakeAdding 0.3 + 0.9 = 0.12.

✓ Instead0.3 + 0.9 = 1.2: 12 tenths is 1 whole and 2 tenths.

Ten tenths regroup into one whole, just as ten ones regroup into one ten.

✗ MistakeWriting 310 as 3.10.

✓ Instead310 = 0.3.

3.10 means 3 wholes and 10 hundredths. Three tenths is less than 1, so the ones digit is 0.

Not to be confused with

Tenthsvs.Tens

Tens are groups of ten (the 4 in 47 is 4 tens = 40). Tenths are parts of one (the 4 in 0.4 is 4 tenths). The “th” makes it a part.

Tenthsvs.Hundredths

Hundredths are 10 times smaller than tenths: 0.1 = 10 hundredths, while 0.01 is one hundredth.

Quick check: 3 questions

Question 1 of 3

What does the 9 mean in 3.92?

Show answer and explanation

Answer: D. The 9 is the first digit after the point, so it is in the tenths place: 9 tenths = 0.9. 9 tens is 90, 9 ones is 9, and 9 hundredths would be the second place after the point.

Question 2 of 3

Which decimal is equal to 1410?

Show answer and explanation

Answer: B. 14 tenths = 10 tenths + 4 tenths = 1 whole and 4 tenths = 1.4. 0.14 is 14 hundredths, and the others move the point too far.

Question 3 of 3

Which list is in order from least to greatest?

Show answer and explanation

Answer: C. Compare tenths: 0.45 has 4 tenths, 0.5 has 5, 0.6 has 6. So 0.45 < 0.5 < 0.6. Choice A treats 45 as bigger than 5, and D is greatest to least.

Tenths: frequently asked questions

What is the difference between tens and tenths?

Tens are big and tenths are small. The tens place is two places left of the decimal point, and a digit there counts groups of ten: the 3 in 35 is 30. The tenths place is the first place right of the point, and a digit there counts tenths of one: the 3 in 0.3 is three tenths. The ending “th” signals a part of one.

How do you write tenths as a decimal?

Put the number of tenths in the first place after the decimal point. Four tenths is 0.4, and nine tenths is 0.9. If there are 10 or more tenths, regroup each 10 tenths as 1 whole: 23 tenths is 2 wholes and 3 tenths, which is 2.3.

What does rounding to the nearest tenth mean?

It means keeping exactly one digit after the decimal point. Look at the hundredths digit: if it is 5 or more, add 1 to the tenths digit; if it is 4 or less, keep the tenths digit and drop everything after it. So 8.73 rounds to 8.7, and 8.75 rounds to 8.8.

Practice and tools

Fraction, Decimal and Percent CalculatorTurn tenths into fractions and percents Rounding CalculatorRound to the nearest tenth

Sources

Updated November 2026·Reviewed by the Effortless Math team·Standards: CCSS 4.NF.C.6, CCSS 5.NBT.A.1

Cite this entry

Effortless Math Team. “Tenths.” Effortless Math Dictionary. Updated November 2026. https://www.effortlessmath.com/math-dictionary/tenths/

Flashcard

TermTenths10 equal parts of one

DefinitionOne of 10 equal parts of a whole, written 1/10 or 0.1. In 4.7, the 7 is in the tenths place and means 0.7.

Study the full deck

Browse all terms in the Math Dictionary · More number system terms · Random term

FractionA fraction is a number that names equal parts of a whole, written ab. The bottom number, the denominator, tells how many equal parts make one whole; the top number, the numerator, tells how many of those parts you have. So 34 means 3 of 4 equal parts. Every fraction is also a point on the number line.Number System · Grade 3, Grade 4, Grade 5Decimal PointA decimal point is the dot that separates the whole-number part of a number from its fractional part. Digits to its left are ones, tens and hundreds; digits to its right are tenths, hundredths and thousandths. In 46.25 the point sits between 6 ones and 2 tenths, and you read it aloud as “and”.Number System · Grade 4, Grade 5, Grade 6HundredthsHundredths are the parts you get when one whole is split into 100 equal parts; one hundredth is 1100 or 0.01. The hundredths place is the second digit to the right of the decimal point, so in 3.47 the 7 means 7 hundredths. One cent is one hundredth of a dollar.Number System · Grade 4, Grade 5, Grade 6NumberA number is an amount or value used to count, measure, order and compare. We write numbers with digits (7), words (seven) or other symbols, but the number itself is the amount: 7 dots, the word seven and the numeral 7 all show the same number. Numbers include whole numbers, fractions, decimals and negatives.Number System · Kindergarten, Grade 1, Grade 2RoundingRounding replaces a number with a nearby number that is easier to use, to a chosen place value. Look at the digit immediately to the right of that place: 5 or more rounds up, 4 or less rounds down. So 47 rounds to 50 to the nearest ten, and 3.68 rounds to 3.7 to the nearest tenth.Number System · Grade 3, Grade 4, Grade 5Simplest FormSimplest form is the way of writing a fraction so its numerator and denominator have no common factor other than 1. To get there, divide the top and bottom by their greatest common factor: 68 = 6 ÷ 28 ÷ 2 = 34. The value stays the same; only the numbers get smaller. It is also called lowest terms.Number System · Grade 4, Grade 5, Grade 6Place ValuePlace value is the value of a digit based on its position in a number. In 3,507 the 5 is worth 500, because it sits in the hundreds place. Each place is worth 10 times the place to its right: ones, tens, hundreds, thousands, and after the decimal point, tenths and hundredths.Number System · Grade 3, Grade 4, Grade 5PercentA percent is a number out of 100. Percent means per hundred, so 25% means 25 out of 100, or 25100 = 0.25. To find a percent of a quantity, change the percent to a decimal and multiply: 20% of 80 is 0.20 × 80 = 16. The symbol for percent is %.Number System · Grade 5, Grade 6, Grade 7Unit FractionA unit fraction is a fraction with a numerator of 1, such as 12, 15 or 112. It names one equal part of a whole split into that many parts. The bigger the denominator, the smaller the unit fraction, and every fraction ab is a copies of 1b.Number System · Grade 3, Grade 4, Grade 5DecimalA decimal is a number written with a decimal point to show parts of a whole. Decimals use place value to represent tenths, hundredths, thousandths and more: in 3.14, the 1 means 1 tenth and the 4 means 4 hundredths. So 0.75 = 75100, and 0.5 is one half.Number System · Grade 4, Grade 5, Grade 6Number LineA number line is a straight line with numbers placed at equal distances along it, so every point stands for a number. Zero sits in the middle, positive numbers go to the right and negative numbers to the left. Numbers increase from left to right, so a number line shows order, distance and adding as moving.Number System · Grade 2, Grade 3, Grade 6

Tenths

What are tenths in math?

Tenths in a picture

Formal definition and notation

Key facts

Tenths as fractions and decimals

Try it: count by tenths

Tenths examples, step by step

Example 1: Decimal to fraction

Example 2: Adding tenths with regrouping

Example 3: Rounding to the nearest tenth

Common mistakes

Not to be confused with

Quick check: 3 questions

Tenths: frequently asked questions

What is the difference between tens and tenths?

How do you write tenths as a decimal?

What does rounding to the nearest tenth mean?

Related terms

Practice and tools

Sources

Flashcard

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