Answer:
0.6472 = 64.72% probability that a randomly selected page does not need to be retyped.
Step-by-step explanation:
In a Poisson distribution, the probability that X represents the number of successes of a random variable is given by the following formula:
In which
x is the number of sucesses
e = 2.71828 is the Euler number
is the mean in the given interval.
Poisson distribution with an average of three errors per page
This means that 
What is the probability that a randomly selected page does not need to be retyped?
Probability of at most 3 errors, so:

In which
Then

0.6472 = 64.72% probability that a randomly selected page does not need to be retyped.
-12 is a Irrational number
7 strawberries. 30 plus 12 is 42. 42 divided by 6 equals to seven. 7 strawberries each.
They estimated it by the last digit in 68,658. Since 8 is over 5, you round it up to 70,000. Another way to put it is that 68,658 is closer to 70,000 than it is to 68,000. Does that make sense?