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Bunuel
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sun01
Bunnel,

One thing, I didn't get it here, is

Why P= p1x p2?

why it can't be P = P1+P2.

I am missing some fundamentals thing. Please explain to clear my concept.

Principle of Multiplication
If an operation can be performed in ‘m’ ways and when it has been performed in any of these ways, a second operation that can be performed in ‘n’ ways then these two operations can be performed one after the other in ‘m*n’ ways.

Principle of Addition
If an operation can be performed in ‘m’ different ways and another operation in ‘n’ different ways then either of these two operations can be performed in ‘m+n’ ways (provided only one has to be done).

Check below post for more:
Probability Made Easy!

Theory on probability problems

Data Sufficiency Questions on Probability
Problem Solving Questions on Probability

Tough Probability Questions
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I have edited the question and the solution by adding more details to enhance its clarity. I hope it is now easier to understand.
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