SME
Grade 7 Math · Problem type
Circumference or area?
Use this for “Is it circumference or area?” before choosing the formula.
Sort
Does the question ask for circumference or area?
Tap a card, then tap its group.
Assumptions
•
Circumference is a length: the distance around, C = πd. Its units are cm, m, ft.
•
Area is a surface: the space inside, A = πr². Its units are square: cm², m², ft².
← Previous lesson
Circumference is proportional to diameter
Next lesson →
Supplementary, complementary, vertical and adjacent angles
Topic check
See what you know: 5 questions on this topic
New questions each time. Pass to mark it complete.
Refresh
Related lessons
Circumference and area of circles
Main lesson
Circumference and wheels
Use this for “A 28-inch wheel turns 25 times. How far does the bike go?”
A circle in a square
Use this for “A circle of radius 5 is inside a square. What area is left in the corners?”
Circumference is proportional to diameter
Use this for “A circle has diameter 4. What is its circumference, and where is it on the graph?”