Answer:
The amount of weight he has lost in 3 months is 1.215 stone or 1 stone 3 pounds
Step-by-step explanation:
From the above question, we are to calculate the amount of weight he has lost in three months
1 stone = 14 pounds
Let's convert all the weight lost to stone
At the start of the diet keirin weighted 14 stone 13 pounds
14 pounds = 1 stone
13 pounds = x
Cross Multiply
14x = 13
x = 13/14
x = 0.9285714286 stone
Approximately = 0.929 stone
Hence:
14 stone 13 pounds = 14 + 0.929 = 14.929 stone
Three months later he weighted 13 stone 10 pounds
14 pounds = 1 stone
10pounds = x
Cross Multiply
14x = 10
x = 10/14
x = 0.7142857143 stone
Approximately = 0.714 stone
Hence:
13 stone 10 pounds = 13 + 0.714 = 13.714 stone
The amount of weight he has lost is calculated as:
14.929 stone - 13.714 stone = 1.215 stone or 1 stone 3 pounds
Answer:
Where
and 
We are interested on this probability

And the best way to solve this problem is using the normal standard distribution and the z score given by:

If we apply this formula to our probability we got this:
And we can find this probability using the complement rule:

Step-by-step explanation:
Previous concepts
Normal distribution, is a "probability distribution that is symmetric about the mean, showing that data near the mean are more frequent in occurrence than data far from the mean".
The Z-score is "a numerical measurement used in statistics of a value's relationship to the mean (average) of a group of values, measured in terms of standard deviations from the mean".
Solution to the problem
Let X the random variable that represent the variable of interest of a population, and for this case we know the distribution for X is given by:
Where
and 
We are interested on this probability

And the best way to solve this problem is using the normal standard distribution and the z score given by:

If we apply this formula to our probability we got this:
And we can find this probability using the complement rule:

1) in one minute for first wiil be 1/20
the other 1/30, it means that A paint in one minute 1/20 and B 1/30 then A+B in one minute 1/20 + 1/30 = 3+2/60 = 5 / 60, 5/60 = 1/12
if in one min they make 1/12 then in 12 min they paint all the wall
A function has a vertical asymptote where it is not defined, and the logarithm is defined only if its argument is strictly positive: it has a vertical asymptote if its argument is zero, and is not defined if its argument is negative.
So, you have a vertical asymptote where

The 3rd one I thinkkkkk ??