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:
-7
Step-by-step explanation:
Let the number be x
So we get equation : 3x + 8 = -13
Thus, 3x = -13-8 = -21
So, x = (-21)/3
Hence the required number is -7
My mom has trouble understanding math... I decided to give her an easy equation. 3/6 km+1/5km = 15/40 +8/40. She asked me what I did. I told her that I multiplied both equations to get a denominator of 40. Then she said "what about those top ones" "oh... well" I said " whatever I multiplied to the bottom I have to do to the top!" Anyway back to the problem. Well... somehow all of this equals 23/40. This is because when you add 15 + 8 that equals 23! So wait a sec what is this on the bottom she asked. well... I am unsure why don't you tell me. She said that the 4 needed to have been added to it.. but the four was too much so they took away one. Good enough! The answer is 3 and 17/40
The value of .
Solution:
Given data:
To find the value of
Using trigonometric identity,
Substitute in the identity, we get
1 can be written as .
Do cross multiplication.
Denominators are same, so you can add the fractions.
Taking square root on both sides, we get
Option B is the correct answer.
Hence the value of .