CHAPTER 14 FACTORISATION
CHAPTER 13 DIRECT AND INVERSE PROPORTIONS
x and y are said to be in direct proportion if x/y = k or x = ky.
If x and y are in direct proportion, x1/y1=x2/y2
x and y are said to be in inverse proportion if xy=k.
CHAPTER 11 MENSURATION
AREA OF TRAPEZIUM
Area of trapezium = half the sum of the lengths of parallel sides x perpendicular distance between them
The surface of a solid is the sum of the areas of its faces.
CHAPTER 10 VISUALISING SOLID SHAPES
When a solid object has only two measurements it is called a 2 dimensional shape.
When a solid object has three measurements- length, breadth and depth, it is called a 3 dimensional shape.
3D shapes objects have a different views from different positions
A map depicts the location of a particular object in relation to other objects.
A polyhedron is a solid made up of polygonal regions called faces. These faces meet at edges and edges meet at vertices. For any polyhedron,
F + V – E = 2
Where ‘F’ stands for the number of faces, V is the number of vertices and E stands for number of edges. This is Euler’s formula.
CHAPTER 9 ALGEBRAIC EXPRESSIONS AND IDENTITIES
CHAPTER 8 COMPARING QUANTITIES
CP= Buying price + Overhead expenses
Sales tax= tax% of Bill Amount
CHAPTER 6 SQUARE AND SQUARE ROOTS
CHAPTER 5 DATA HANDLING
Information collected in the context of a situation to be studied is called data.
GRAPHICAL REPRESENTATION OF DATA
1. Pictograph: Pictorial representation of data using symbols.
2. Bar Graph: Representation of data using bars of uniform width, their heights being proportional to the respective values.
3. Double Bar Graph: A bar graph that shows two sets of data simultaneously is called a double bar graph. This graph is used for comparison of data.
Data that is in an unorganized form is called raw data. Raw data should be organized in order to gain any inference from it.
Frequency gives the number of times a particular entry occurs.
Histogram is a type of bar diagram where the class intervals are shown on the horizontal axis and the heights of the bars show the frequency of the class interval.
There is no gap between the bars as there is no gap between the class intervals.
A circle graph shows the relationship between a whole and its part.
A random experiment is the one whose outcomes cannot be predicted exactly in advance.
Probability of an event= (Number of outcomes that make the event)/(Total number of outcomes of the experiment)
An event is one or more outcomes of an experiment.