Bridges in Mathematics Grade 4, Unit 3: Fractions & Decimals
In this unit, your child sees why fractions like 3/4 and 6/8 name the same amount, compares fractions with different denominators, and connects tenths and hundredths to decimals like 0.62. It builds on the multiplying from the last unit, since equivalent fractions come from multiplying. Next, your child returns to big numbers, adding, subtracting, and measuring.
By Robert “Bobby” BarnettMath teacher, parent, and founder of Bobby’s Math Club
What is my child learning in Unit 3?
- Showing why 3/4 and 6/8 are equivalent fractions, by multiplying the numerator and denominator by the same number. Learn more: Why fractions like 3/4 and 6/8 are equal
- Comparing fractions like 2/3 and 5/6 by finding a common denominator or checking each against 1/2. Learn more: Comparing fractions like 2/3 and 5/6
- Renaming tenths as hundredths, like 3/10 = 30/100, so they can add 3/10 + 4/100 = 34/100. Learn more: Adding tenths and hundredths together
- Writing fractions with a denominator of 10 or 100 as decimals, such as 62/100 = 0.62. Learn more: Writing fractions as decimals, like 0.62
- Comparing decimals like 0.09 and 0.1 by their size, not by how many digits they have. Learn more: Comparing decimals like 0.09 and 0.1
Sample questions to try together
These are real questions from our practice. Tap the speaker to hear one read aloud, or the light bulb for a hint, and talk about the answer together.
Question 1 of 3
What is the missing number? 4/5 = ?/10
- 4
- 9
- 8
How you can help
- Fold two same-size strips of paper, one into fourths and one into eighths. Shade 3/4 and 6/8, line them up, and ask your child why the two shaded parts match.
- Count dimes and pennies together. Put out 3 dimes and 4 pennies and ask your child to write the amount as a fraction of a dollar, 34/100, and as a decimal, 0.34.
- Compare prices under a dollar at the store, like $0.09 and $0.10. Ask which is more and how they know, then try 0.5 and 0.45 without the dollar sign.
Where kids can get stuck
- Thinking 1/8 is bigger than 1/4 because 8 is bigger than 4.
- Adding tops and bottoms straight across, so 3/10 + 4/100 becomes 7/110.
- Writing 7/100 as 0.7, putting the 7 in the tenths place instead of the hundredths place.
Practice makes perfect
Bobby's Math Club has practice problems that adapt to your child’s level, each with a detailed explanation and an easy-to-follow video, so your child can build confidence in these skills one step at a time.
Words your child will hear
- numerator
- The top number of a fraction, telling how many equal parts are counted.
- denominator
- The bottom number of a fraction, telling how many equal parts make one whole.
- equivalent fractions
- Fractions that name the same amount, like 3/4 and 6/8.
- common denominator
- The same denominator shared by two fractions, which makes them easy to compare or add.
- benchmark fraction
- A familiar fraction, like 1/2 or 1, used to compare other fractions.
- tenth
- One of 10 equal parts of a whole, written 1/10 or 0.1.
- hundredth
- One of 100 equal parts of a whole, written 1/100 or 0.01.
- decimal
- A number written with a decimal point, like 0.62, to show parts of a whole.
- decimal point
- The dot that separates the whole number from the tenths and hundredths.
Ready to build your child’s confidence with fractions and decimals?
In Bobby's Math Club, your child practices these skills at just the right level, with a hint when they need one, a clear explanation after every question, and kid-friendly videos. Unlimited practice is free.
Join the club
Written by Robert “Bobby” Barnett
Bobby is an award-winning math teacher, the author of Meet Every Learner’s Needs, and the father of two elementary-school math learners. He uses Bobby’s Math Club with his own kids a few times every week. Learn more or contact Bobby.
Which math standards does Bridges in Mathematics Grade 4 Unit 3 cover?
Bridges in Mathematics Grade 4 Unit 3 covers these math standards. Each one links to what it means, sample questions, and teaching strategies.
- 4.NF.A.1: Find equal fractions, like 3/4 = 6/8, by multiplying top and bottom.
- 4.NF.A.2: Compare fractions with different denominators, like 2/3 and 5/6.
- 4.NF.C.5: Turn tenths into hundredths to add them, like 3/10 + 4/100.
- 4.NF.C.6: Write tenths and hundredths as decimals, like 4/10 = 0.4.
- 4.NF.C.7: Compare decimals to hundredths, like 0.09 and 0.1.
For teachers: Unit names and order vary between editions and districts, so your school’s own materials have the exact sequence. Learn how Bobby's Math Club can help your students grow.