Important Definitions & Formulas: Probability | Mathematics (Maths) Class 10 PDF Download

Probability

• 
• q(not happening) = 1 - p

Sample Space of Coin Toss

• When a coin is tossed, S = {H, T}
• When two coins are tossed simultaneously = {HH, HT, TH, TT}
• When three coins are tossed simultaneously = {HHH, HHT, HTH, HTT, THH, THT, TTH, TTT}

Sample Space of Throwing a Die 

• When a die is thrown once = {1, 2, 3, 4, 5, 6}
• When two dice are thrown simultaneously
  => {(1,1), (1,2), (1,3), ...., (1,6)
  (2,1), (2,2), (2,3), ...., (2,6)
  (3,1), (3,2), (3,3), ...., (3,6)
  (4,1), (4,2), (4,3), ...., (4,6)
  (5,1), (5,2), (5,3), ...., (5,6)
  (6,1), (6,2), (6,3), ...., (6,6)}

Geometric Probability

If the total number of outcomes of a trial in a random experiment is infinite, then the definition of probability is not sufficient to find the probability of an event, in such cases, the definition of probability is modified and the probability so obtained is called geometric probability. The geometric probability p of an event is given by:

Note: Measure means Length, Area or Volume of the region etc.

Probability while Playing Cards

Playing cards consists of 52 cards which are divided into four suits of 13 cards each. Each suit consists of one king, one queen, one jack, one ace and nine other cards numbered from 2 to 10. The four suits are named spadeclub heart and diamond (♦).