1/4 2/8 3/12 4/16 5/20 6/24
-x -2 I think . 3-(-5)= -2 and 2x -3x = -x
Answer: 0.0001
It is unlikely to have a month with no aircraft accidents .
Step-by-step explanation:
Given : Mean number of aircraft accidents = 9 per month
The Poisson distribution formula :-
, where
is the mean of the distribution.
If X = the number of aircraft accidents per month, then the probability that in a month, there will be no aircraft accidents will be :-

Hence, the probability that in a month, there will be no aircraft accidents = 0.0001
Since this is less than 0.5 , therefor it is unlikely to have a month with no aircraft accidents .
Answer:
14 hours
Step-by-step explanation:
Let's call the task 3x
The older bro does twice as younger so it would be 2x long and younger brother work x long
Since the totsl of work is 3x = 21 x woul be 21÷3 = 7
the older brother must work 2 × 7 = 14 hours long