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. Calculate what the diameter of the circle was.
which subtends an angle of 
at the centre. Use the approximation 3.14 for 
and round the result to two decimal places.
of a circle was cut off as shown. The area of the removed parts is 
. Calculate the circumference of the resulting shape.
and round the result to two decimal places.
, the distance between the centre and a chord is 
shorter than the chord of the circle. What is the length of the chord?
, use the approximation 3.14.
and round the result to two decimal places.
, use the approximation of 3.14 and round the result to two decimal places.
in a circle of radius 
.
for 
and round the result to two decimal places.
is 
, and 
is 
.
to be 
.
. Calculate the angle 
subtended at the centre by an arc of length 
. Take 
to be 
.
, calculate the length of the circular arc that subtends an angle of 
at the centre of the circle. Use 
for 
and round your result to two decimal places.
at the centre. The radius of the circle measures 
. Use the approximation 
for 
and round the result to two decimal places.
. The radius r measures 5 cm.
.
. Use the approximation 
for 
.
and the corresponding angle subtended.
of length 
. The corresponding central angle is denoted by 
. The circular arc 
belongs to the bigger circle with the same central angle. Accurately calculate the difference between the two circular arcs.
and circumference 
and area 
, an arc which subtends an angle 
at the centre was cut off. This arc is then used as the radius for a new circle. Accurately calculate the circumference of the new circle.
where the length of the circular arc is equal to three times the radius of the circle. Use approximation 3.14 for 
.
.
represents a quarter of the total circumference of a circle. By calculation, show how much of the area of the circle is represented by the sector described by this arc.
. From it, a sector with a central angle of 
was cut off. Calculate the area of the rest of the circle.
. The central angle 
is equal to 120°. Calculate the length of the minor arc with the corresponding central angle 
. It is considered that three times the angle 
is ten times greater than the angle 
. Calculate how long the outer border of the flower is.
, from which arcs subtending an angle of 
are cut off and folded into a flower around a bigger circle, as shown in the diagram below. Calculate the circumference of the flower.
