Answer: 0.72
Step-by-step explanation:
Given : The chance of rain today = 0.70
Then , the chance for no rain today = [tex]1-0.70=0.30[/tex]
The chance of rain tomorrow = 0.40
The chance for no rain tomorrow =[tex]1-0.40=0.60[/tex]
We assume that the event that it rains today is independent of the event that it rains tomorrow.
The probability that there will be no rain today and tomorrow is given by :-
[tex]\text{P(not today)}\times\text{P(not tomorrow)}\\\\=0.3\times0.6=0.18[/tex]
Now, the probability that there will be no rain today or tomorrow is given by :-
[tex]\text{P(not today or tommorow)}=\text{P(today)+P(tomorrow)-P(today and tomorrow)}\\\\\Rightarrow\text{P(not today or tommorow)}=0.30+0.60-0.18=0.72[/tex]
Hence, the probability that there will be no rain today or tomorrow = 0.72
