Answer:
95.15%
Step-by-step explanation:
We have that the mean (m) is equal to 20, the standard deviation (sd) 3
They ask us for P (x <25)
For this, the first thing is to calculate z, which is given by the following equation:
z = (x - m) / sd
We have all these values, replacing we have:
z = (25 - 20) / (3)
z = 1.66
With the normal distribution table (attached), we have that at that value, the probability is:
P (z <1.66) = 0.9515
Which means that the probability that it arrives before 25 minutes is 95.15%
Answer:
2 ; 10
Step-by-step explanation:
a + B = 12
a - B = 8
a = 12 - B
(12 - B) - B = 8
a = 12 - B
12 - 2B = 8
B = 2
A = 10
Answer:
Length = 27 metres
Width = 9 metres
Step-by-step explanation:
Consider the width to be x.
Then the length will be 3x.
The perimeter is 66m when the width is increased by 1m and the length is decreased by 4m.
So the dimensions will become:
Length=3x-4
Width=x+1
Now solve for the variable x using the formula for perimeter of a rectangle:
P = 2(l+b)
66 = 2(3x-4+x+1) (Divide both sides by 2 and simplify the parentheses)
33 = 4x-3 (Add 3 to both sides)
36 = 4x (Divide both sides by 4)
x = 9
Now plug-in the value of x into the original dimensions which were:
Length=3x
Width=x
So the dimensions are:
Length = 27 metres
Width = 9 metres
Answer:
false
Step-by-step explanation:
i think the answer is false srry if i am wrong
3.10/155= 0.02 } subtract = 0.07 more
7.65/85= 0.09 }
