Area of quadrilaterals :
A quadrilateral is a flat shape with four straight sides.
Types of quadrilaterals :
A square has got 4 sides of equal length and 4 right angles (right angle = 90 degrees).
A Rhombus has got 4 sides of equal length and opposite sides are parallel and angles are equal.
The rectangle (oblong) contains 4 right angles (an angle of 90˚). It has got 2 pairs of equal sides and 4 right angles
A parallelogram is a rectangle that has been pushed over. Opposite sides are the same length and they are parallel.
Area of square = 4a
Area of rectangle = Length x width
Area of parallelogram = base x height
Area of rhombus = (1/2) x (d₁ x d₂)
Area of trapezium = (1/2) x h (a+ b)
Example 1 :
A window shaped like a parallelogram has an area of 18 ⅓ square feet. The height of the window is 3 ⅓ feet. How long is the base of the window?
Area of the parallelogram = base x height
Area of window = 18 ⅓ square feet
height of window = 3 ⅓
Let "x" be the base of the parallelogram
x x 3 ⅓ = 18 ⅓
x x 10/3 = 55/3
x = (55/3) x (3/10)
x = 11/2
x = 5 ½ feet
Hence, the length of window is 5 ½ feet.
Example 2 :
A section in a stained glass window is shaped like a trapezoid. The top base is 4 centimeters and the bottom base is 2.5 centimeters long. If the area of the section of glass is 3.9 square centimeters, how tall is the section?
Area of the trapezoid = (1/2) x h (a + b)
length of top base (a) = 4 cm
length of bottom base = 2.5 cm
Area of the section = 3.9 square centimeters
(1/2) x h (4 + 2.5) = 3.9
(1/2) x h (6.5) = 3.9
h = (3.9 x 2) / 6.5
h = 1.2 cm
Example 3 :
A parallelogram-shaped field in a park needs sod. The parallelogram has a base of 21.5 meters and a height of 18 meters. The sod is sold in pallets of 50 square meters. How many pallets of sod are needed to fill the field?
Base length of the park = 21.5 m
height = 18 m
Area of parallelogram shaped field = base x height
= 21.5 x 18
Number of pallets required to fill the field = 387/50
Hence 8 pallets are needed to fill the field.
After having gone through the stuff given above, we hope that the students would have understood "History of statistics".
Apart from the stuff given above, if you want to know more about "History of statistics", please click here
Apart from the stuff given in this section, if you need any other stuff in math, please use our google custom search here.
You can also visit our following web pages on different stuff in math.
APTITUDE TESTS ONLINE
ACT MATH ONLINE TEST
TRANSFORMATIONS OF FUNCTIONS
ORDER OF OPERATIONS
Converting customary units worksheet
Customary units worksheet
Integers and absolute value worksheets
Nature of the roots of a quadratic equation worksheets
Trigonometry heights and distances
MATH FOR KIDS
Word problems on linear equations
Trigonometry word problems
Word problems on mixed fractrions
Converting repeating decimals in to fractions