Perimeter and Area Flashcards
If a square has sides 3cm long, what is its area?
9cm2
A woman takes her dog for a walk around the edge of a rectangular park that is 500m wide and 1.5km long and ends where she started. How far has she walked?
4km or 4000m
How would you find the area of any triangle?
Times the length of its base by its height, then divide by two
What is the area of this shape?
28cm2
What is the perimeter of this shape?
22cm
What units is perimeter usually measured in?
Millimetres (mm), centimetres (cm) or metres (m)
What units do we usually measure area in?
Centimetres squared (cm2) or Metres squared (m2).
What is the area of this rectangle?
160cm2
What is the area of this triangle?
14cm2
This circle has a radius of 4cm. What is its area?
50.256cm2
What is area?
The amount of space inside a 2D shape
What is perimeter?
The total length of all of a 2D shapes sides.
The square below has an area of 36cm2. What length are its sides?
All four sides are 6cm long
How would you calculate the area of a rectangle?
Times its width by its length
How would you calculate the area of a shape like the one below?
Split the shape into two rectangles, calculate the area of each then add them together
How would you calculate the area of a semicircle like the one below?
A semicircle is half of a circle, so if we calculate the area of a full circle with the same radius and half it, we will find the area of the semicircle.
What is the area of this trapezium?
Formula for the area of a trapezium is h(b+a) ÷ 2
Area = 38cm2
A section of pavement 5m wide and 300m long requires paving with 0.5m x 0.5m square paving slabs. How many paving slabs will be needed to pave the enture section of pavement?
Area of pavement = 5m x 300m = 1500m2
Area of a single paving slab = 0.5m x 0.5m = 0.25m2
Number of slabs required to cover the pavement = 1500m2÷ 0.25m2 = 6000
Ali bakes the cake below. He would like to wrap a red ribbon around it as shown, but needs to calculate how long the piece of ribbon needs to be to fit all the way around the cake. How could he do this, and how long will the ribbon need to be?
The cake is a rectangle when viewed from above, and the length of the ribbon will have to equal the perimeter of that rectangle.
The ribbon will have to be 100cm long
What is the formula for finding the area of a circle?
Area of a circle = πr2
What is the formula for finding the circumference of a circle?
Circumference = πD
Or 2πr
What is the formula for the area of a triangle?
Area of a triangle = b x h ÷ 2
What is the formula for the area of a parallelogram?
Area of parallelogram = Base x Perpendicular Height
