## Tips to solve Permutation and Combination Problems

Factorial Notation:Let n be a positive integer. Then, factorial n, denoted n! is defined as: n! = n(n – 1)(n – 2) … 3.2.1. Examples: We define 0! = 1.…

## Tips and Tricks on H.C.F and L.C.M

Factors and Multiples:If number a divided another number b exactly, we say that a is a factor of b.In this case, b is called a multiple of a. Highest Common Factor (H.C.F.) or Greatest Common Measure (G.C.M.) or Greatest…

## Tricks to Solve Problems on Square Root & Cube Root

Square Root If x2 = y, we say that the square root of y is x and we write √y = (+/-)x Thus, √4 = 2, -2 √9 = 3, -3 √196 = 14, -14 Cube Root: The…

## Short Notes and Board Exams Questions: Life Processes

All living things perform certain life processes like growth, excretion, respiration, circulation etc. All the processes like respiration, digestion, which together keep the living…

## Short Notes and Board Exam Questions : Sources Of Energy

• Energy comes in different forms and one form can be converted into another. • A source of energy is one which provide adequate amount…

## Human Eye and Colourful World: Important Questions for Board Exams

CHECK YOUR KNOWLEDGE VERY SHORT ANSWER TYPE QUESTIONS 1. What type of lens is used to correct (a) Hypermetropia, (b) Myopia ? 2. Name the…

## Short Notes On: The Human Eye and The Colourful World

Human eye : The sense organ that helps us to see. • Located in eye sockets in skull. • Diameter of eye ball – 2.3…

## Control and Coordination, Important Questions For Board Exams

QUESTIONS VERY SHORT QUESTIONS (1 Mark) 1. Where is auxin synthesized in plants ? 2. Which gland is known as master gland ? 3. Name…

## Short Notes on control and coordination

Control and Coordination • All the living organisms respond and react to changes in the environment around them. • The changes in the environment to…

## नियन्त्रण एवं समन्वय ( बोर्ड परीक्षा में पूछे गए कुछ महवपूर्ण प्रश्न )

अतिलघुत्तरीय प्रश्न  ( 1 अंक ) 1.पौधों में ऑक्सीजन कहाँ संश्लेषित होता हैं ? 2.कौन सी ग्रंथि मास्टर ग्रंथि कहलाती हैं ? 3.रक्त में शकरा की…