Concept 3 of 6
Thirds and Fourths
Today's big idea
3 equal parts are thirds; 4 equal parts are fourths.
Each third is 1/3; each fourth (quarter) is 1/4.
How it works
👀 What's going on?
Cut into 3 equal parts, or into 4. Each size gets its own name.
💡 Here's the trick
3 equal parts make thirds, and each is 1/3. 4 equal parts make fourths, also called quarters, and each is 1/4.
A chocolate split into 4 equal parts gives 4 quarters.
✍️ Try it
A cake is cut into 3 equal parts. Each part is one… → third.
⚠️ Watch out
The more equal parts you cut, the smaller each piece becomes.
Watch me solve one
Quanta solves it
“Watch how I think through one of these — then you try.”
THE PROBLEM
“A cake is cut into 3 equal parts. Each part is one…?”
- 1
Count the equal parts
There are 3 equal parts.
- 2
Name for 3 parts
3 equal parts are called thirds.
- 3
So each part is
one third (1/3).
- 4
Answer ✓
third
Now you try one — same steps, different story 👇
See it in action
⚡ Time to play!
The whole is in 2 equal parts. Tap the name.
Quick check
✅ VERIFICATION
A whole is cut into 4 equal parts. Each part is one…
⚡ Finish the activity above first to answer.
Keep going!
Up next: Name the Fraction
Top = shaded parts, bottom = parts in all.