Year 4 · Fractions · Summary

Year 4 Fractions: summary and key words

Part of the Year 4 fractions chapter. Chapter overview · whole chapter on one page

Chapter summary

Skill	Method
Naming fractions	Bottom number (denominator) = number of EQUAL parts in the whole. Top number (numerator) = parts we have. 3 of 8 equal parts = 3/8.
Fractions of a set	Whole set on the bottom, the part you want on the top: 3 red counters out of 8 counters = 3/8.
Fraction of an amount	Divide by the bottom number to find one part. Multiply by the top number. 3/4 of 20: 20 ÷ 4 = 5, 5 × 3 = 15.
Fraction left	Find the amount used, then take it away from the whole. Or find the other parts: (bottom − top) parts.
Equivalent fractions	Multiply (or divide) the top AND the bottom by the same number. 1/2 = 2/4 = 4/8. Fifths and tenths: 1/5 = 2/10. Never add.
Add, same denominator	Add the top numbers. Keep the bottom number. 2/7 + 3/7 = 5/7. If the answer is 8/8, that is 1 whole.
Subtract, same denominator	Subtract the top numbers. Keep the bottom number. 1 whole = 5/5, so 1 − 2/5 = 3/5.
Compare, same denominator	The bigger top number is the bigger fraction: 5/8 > 3/8.
Compare unit fractions	The bigger the bottom number, the smaller the fraction: 1/8 < 1/4. A fraction wall shows it.
Compare / order, different denominators	Change to equivalent fractions with the same bottom number (3/4 = 6/8), then compare the top numbers. Compare with 1/2 as a quick check.
Improper fractions and mixed numbers	7/4 = 1 3/4. Improper → mixed: divide the top by the bottom, the remainder goes on top. Mixed → improper: whole × bottom + top.
Counting in fractions	Count in steps of the unit fraction. After the last fraction comes a whole: 3/4, 1, 1 1/4. Count back the same way.
Tenths and hundredths	10 tenths = 1. 100 hundredths = 1. 1/10 = 10/100. 1/10 ÷ 10 = 1/100. In a hundred square, a row is a tenth and a square is a hundredth.

Can you…?

I can name a fraction of a shape or a set, and I know the parts must be equal.
I can find a unit fraction of an amount by dividing.
I can find a non-unit fraction of an amount: divide by the bottom number, then multiply by the top number.
I can use fractions of money and measures to solve problems.
I can show equivalent fractions with bars, a fraction wall and a number line, and fill in missing numbers.
I can add and subtract fractions with the same denominator, including making a whole.
I can compare and order fractions with the same denominator, and use a fraction wall or equivalent fractions when they differ.
I know that a bigger denominator does not mean a bigger fraction.
I can write improper fractions and mixed numbers from pictures and number lines, and change between them.
I can count up and down in tenths and hundredths, including past 1.
I know that 10 hundredths make 1 tenth.

Key terms

Fraction: A part of a whole, or of a set, cut into equal parts.
Equal parts: Parts that are exactly the same size.
Denominator: The bottom number of a fraction. It says how many equal parts there are altogether.
Numerator: The top number of a fraction. It says how many parts we have.
Unit fraction: A fraction with 1 on the top, like 1/5.
Non-unit fraction: A fraction with a top number that is not 1, like 3/5.
Equivalent fractions: Fractions that show the same amount, like 1/2 and 2/4.
Fraction wall: A chart of bricks that shows fractions of one whole in rows.
Whole: One complete thing. 4/4 and 10/10 both equal 1 whole.
Compare: To say which of two numbers or fractions is bigger.
Order: To put numbers or fractions in a list from smallest to biggest, or biggest to smallest.
Improper fraction: A fraction whose top number is the same as or bigger than the bottom number, like 7/4.
Mixed number: A whole number and a fraction together, like 1 3/4.
Tenth: One of 10 equal parts of a whole: 1/10.
Hundredth: One of 100 equal parts of a whole: 1/100.
Bar model: A drawing of a bar cut into equal parts that shows a fraction of an amount.