Answer:
Addition used for 'either or' events , Multiplication used for 'and' events
Step-by-step explanation:
Addition is used when Probability is of 'one event or other event'
Multiplication is used when Probability is of 'one event & other event'
Ex : Probability of A winning = 0.4
Probability of B winning = 0.3
Probability (A or B winning) = 0.4 + 0.3 = 0.7
Probability (A & B winning) = 0.4 x 0.3 = 0.12