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Study Material and Tips

### Tips to Solve Problems on Probability

Experiment : An operation which can produce some well-defined outcomes is called an experiment. Random Experiment :An experiment in which all possible outcomes are know and the exact output cannot be predicted in advance, is called a random experiment. Ex : i.Tossing a fair coin. ii.Rolling an unbiased dice. iii.Drawing a card from a pack of well-s...

### Tips to Solve Problems on Pipes and Cisterns

1.Inlet : A pipe connected with a tank or a cistern or a reservoir, that fills it, is known as an inlet. Outlet : A pipe connected with a tank or cistern or reservoir, emptying it, is known as an outlet. 2.(i) If a pipe can fill a tank in x hours, then: part filled in 1 hour = 1/x (ii) If a pipe can empty a tank in y hours, then: part emptied in 1 ...

### Tips to Solve Problems on Permutations and Combinations

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. 4! = (4 x 3 x 2 x 1) = 24. 5! = (5 x 4 x 3 x 2 x 1) = 120. Permutations: The different arrangements of a given number of things by taking some or all at a time, are called permutations. Ex1 : All pe...

### Tips to Solve Problems on Heights and Distances

1.In a right angled,where 2. Trigonometrical Identities : 3. Values of T-ratios : 4. Angle of Elevation: Suppose a man from a point O looks up at an object P, placed above the level of his eye. Then, the angle which the line of sight makes with the horizontal through O, is called the angle of elevation of P as seen ...

### Tips to Solve Problems on Compound Interest

Let Principal = P, Rate = R% per annum, Time = n years. When interest is compound Annually: Amount = When interest is compounded Half-yearly: Amount = When interest is compounded Quarterly: Amount = When interest is compounded Annually but time is in fraction, say 3 years. Amount = When Rates are different for diff...