Answer:
mean if 7
Step-by-step explanation:
the mean is 7
Answer:
Step-by-step explanation:
From the given information:
the mean 
= 2300
Standard deviation = 
Standard deviation (SD) = 214.4761
TO find:
a) 



From the Z-table, since 5.595 is > 3.999

P(x > 3500) = 0.0001
b)
Here, the replacement time for the mean 
= 0.25
Replacement time for the Standard deviation 

For 115 component, the mean time = (115 × 20)+(114×0.25)
= 2300 + 28.5
= 2328.5
Standard deviation = 
= 
= 
= 
= 
= 214.482
Now; the required probability:




From the Z-table, since 8.376 is > 3.999
P(x > 4125) = 1 - 0.9999
P(x > 4125) = 0.0001
Answer:

Step-by-step explanation:
So we have the equation:

And we want to solve for x. In other words, we want to isolate the x-variable.
So, add 2y to both sides of the equation.

On the left, the 2y cancel. Simplify the right:

And we're done!
Let lucy = l & neighbour= n
l = n +4
l + n= 14 years
substitute l with n +4
(n +4) + n = 14
2n +4 =14
n=5 years
l = n + 4 lets substitute n with 5
l = 5 + 4
lucy = 9 years
Answer:
line a and b are parallel, there is no perpendicular lines
Step-by-step explanation:
Looking at the slope of each line, you can identify whether the lines are parallel, perpendicularlar, or neither.
When the slopes are the same, they are parallel.
When the slopes have opposite sign and numerator and denominator flipped, they are perpendicular. Ex.
and
are perpendicular slopes.
Finding slope is using the formula: 
Line a has slope
= 
Line b also has slope 
Line c has slope 2
Since slope of line a and b are same, they are parallel.
Line c is not perpendicular to line a and b because the slope should have opposite sign and numerator and denominator flipped, which is 4 not 2.