Answer:
As both the mean and standard deviation are in the desired ranges, the tool passes the technical control.
Step-by-step explanation:
Mean of the batch:
The mean of the batch is the sum of all values divided by the number of items. So

Mean in the desired interval.
Standard deviation:
Square root of the sum of the difference squared between each term and the mean, divided by the number of items. So

As both the mean and standard deviation are in the desired ranges, the tool passes the technical control.
I don't know what your looking for, so be more specific, but I'm assuming your solving for x, so that's would be
x = -1
The formula for compounded continuously is :

Here the Amount triples , so let us say the new amount A=3P

Cancelling P from both sides we get,

Now here we are given rate is 2.75% or 0.0275,

solving for t we get
t=39.95 years
The relation is a function