union of two independent probabilistic event I have following question:
Suppose we have two independent events whose probability are the following: $P(A)=0.4$ and $P(B)=0.7$. 
We are asked to find $P(A \cap B)$ from probability theory. I know that $P(A \cup B)=P(A)+P(B)-P(A \cap B)$. But surely the last one is equal zero so it means that  result should be $P(A)+P(B)$ but it is more than $1$ (To be exact it is $1.1$). Please help me where i am wrong?

If the events $A$ and $B$ are independent, then $P(A \cap B) = P(A) P(B)$ and not necessarily $0$.
You are confusing independent with mutually exclusive.
For instance, you toss two coins. What is the probability that both show heads? It is $\frac{1}{2} \times \frac{1}{2}$ isn't it? Note that the coin tosses are independent of each other.
Now you toss only one coin, what is the probability that it shows both heads and tails?
