We need to 'standardise' the value of X = 14.4 by first calculating the z-score then look up on the z-table for the p-value (which is the probability)
The formula for z-score:
z = (X-μ) ÷ σ
Where
X = 14.4
μ = the average mean = 18
σ = the standard deviation = 1.2
Substitute these value into the formula
z-score = (14.4 - 18) ÷ 1..2 = -3
We are looking to find P(Z < -3)
The table attached conveniently gives us the value of P(Z < -3) but if you only have the table that read p-value to the left of positive z, then the trick is to do:
1 - P(Z<3)
From the table
P(Z < -3) = 0.0013
The probability of the runners have times less than 14.4 secs is 0.0013 = 0.13%
Answer:
r = 0.7 units
Step-by-step explanation:
C/27 = r
20/27 = 0.7
I'm pretty sure that the answer to the fudge cakes is 8 friends
Answer:
3.5
Step-by-step explanation:
2(5x-9)=17
10x-18=17
+18
10x=35
÷10
x=3.5
or
2(5x-9)=17
÷2
5x-9=8.5
+9
5x=17.5
÷5
x=3.5
Answer:
Step-by-step explanation:
0.2(x – 4.5) + 1.7 = 9.6
0.2*x - 0.2*4.5 + 1.7 = 9.6
0.2x - 0.9 + 1.7 = 9.6
0.2x + 0.8 = 9.6
0.2x = 9.6 - 0.8
0.2x = 8.8
x = 8.8/0.2 = 8.8*10/0.2*10
x = 88/2
x = 44