Understanding Pi and Circle Formulas

What does the symbol π (pi) represent?

• The size of a triangle

• A special number used in circles

• The length of a line

• The area of a square

When do we usually use π = 22/7?

• When the number can be divided by 5

• When the radius or diameter can be divided by 7

• When we don’t want decimals

• When the circle is very big

When do we usually use π = 3.14?

• When we have a radius that can be divided by 7

• When we want an exact value

• When we need a quick and simple calculation

• When the circle is tiny

Which formula is used to find the circumference of a circle?

• π × r²

• 2 × π × r

• π ÷ r

• 2 × r² × π

Which formula is used to find the area of a circle?

• π × r²

• 2 × π × r

• π × d

• π ÷ d²

Which one measures around the circle?

• Radius

• Diameter

• Circumference

• Area

Which one measures inside the circle?

• Radius

• Area

• Circumference

• Diameter

When do we use the radius in a formula?

• When we measure half the distance of a circle

• When we measure the full line across

• When we count the angles

• When we find the square of the circle

When do we use the diameter instead of the radius?

• When the problem gives the full line through the center

• When the circle is very small

• When there is no center point

• When π = 22/7

Which statement is true?

• The diameter is half the radius

• The radius is half the diameter

• The radius and diameter are the same

• The radius is always bigger