The Area of an Ellipse

• Put the ellipse inside the smallest rectangle you can
• Work out the area of the rectangle (by multipling the lengths of the sides together)
• Divide the area of the rectangle by $4$
• Finally multiply by pi!

If putting the ellipse into a rectangle looks too tough, you can just measure how long it is to get $A$, and then measure how fat it is to get $B$, then multiply the two results together. You then divide by $4$ and multiply by pi.

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