Welcome to our Area of a Semi Circle page.
Here you will find a range of free printable area sheets and support,
which will help your child to learn to work out the area of different semi circles.
On this webpage you will find our range of worksheets to help your child learn to work out the area of a range of semi-circles.
These sheets are graded from easiest to hardest, and each sheet comes complete with answers.
Using these sheets will help your child to:
Quicklinks to ...
A semi-circle is a half a circle. The area of a semi-circle is equal to half of the area of a circle with the same radius.
To find the area of a semi circle, follow these simple steps:
Pi (written π) is a special mathematical number which is used to help calculate areas and perimeters of circles.
Pi always has the same value which is 3.141592...
Find the area of the circle below to 1 decimal place.
To find the area of the semi-circle, we need to square the radius first.
3 x 3 = 9.
Next we need to multiply this amount by pi (π).
9 x π = 9π
Finally we need to halve this amount.
½ x 9π = 4.5π = 14.1 (to 1dp)
So the area of this semi-circle is 14.1 cm2.
Find the area of the semi-circle below to the nearest square inch.
To find the area of the semicircle, we need to square the radius first.
6 x 6 = 36
Next we need to multiply this amount by pi (π).
36 x π = 36π
Finally we need to halve this amount.
½ x 36π = 18π = 56.5 (to 1dp)
So the area of this semi-circle is 57 in2 to the nearest square inch.
Find the area of the semi-circle below and give your answer to the nearest whole number.
To find the area of the semicircle, we need to find the radius first.
The radius is equal to half the diameter.
So the radius is half of 18 = 9 cm
Next we need to square the radius.
9 x 9 = 81
Next we need to multiply this amount by pi (π).
81 x π = 81π
Finally we need to halve this amount.
½ x 81π = 40.5π = 127.2 (to 1dp)
So the area of this semi-circle is 127 cm2 to the nearest square cm.
Our Area of a Semicircle Calculator will find the area of any semicircle, if you type in a radius or diameter.
It will take whole numbers, fractions or decimal values.
The best thing about it is that it shows the working out, step-by-step.
We have split the worksheets into 2 different sections:
Sheets 1A and 1B contain circles with the radius marked.
Sheets 2A and 2B contain circles with the diameter marked.
Sheets 3A and 3B contain a mixture of circles with either the diameter or the radius marked.
Sheets 1A and 1B contain straightforward area word problems.
Sheets 2A and 2B contain slightly harder word problems.
Take a look at some more of our worksheets similar to these.
We have a range of other area worksheets and support pages for a range of different 2d shapes.
Here is our selection of free printable perimeter worksheets for 3rd and up.
Using these sheets will help your child to find the perimeter of a range of shapes including rectangles, rectilinear shapes, circles, quadrilaterals and regular shapes.
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How to Print or Save these sheets
Need help with printing or saving?
Follow these 3 easy steps to get your worksheets printed out perfectly!
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