Answer:
translate this to English and I'll help!(:
Answer: in order to qualify, the time must be at least 15.93 minutes
Step-by-step explanation:
Let x be a random variable representing the average response times of fire departments to fire calls. Since it follows a normal distribution, we will determine the z score by applying the formula,
z = (x - µ)/σ
Where
x = sample mean
µ = population mean
σ = population standard deviation
From the information given,
µ = 12.8 minutes
σ = 3.7 minutes
in order to qualify for the special safety award, the probability value would be to the right of the z score corresponding to 80%
The z score corresponding to 80% on the normal distribution table is 0.845
Therefore,
0.845 = (x - 12.8)/3.7
0.845 × 3.7 = x - 12.8
3.13 = x - 12.8
x = 12.8 + 3.13 = 15.93
Answer:
The correct answer is y = 9
Step-by-step explanation:
It is given that,
12/(4y + 6) = 2/7
<u>To find the value of y</u>
12/(4y + 6) = 2/7
By cross multiplying,
12 * 7 = 2 * (4y + 6 )
84 = 8y + 12
8y + 12 = 84
8y = 84 - 12
8y = 72
y = 72/8 = 9
y = 9
Therefore by solving the given expression we get the value of y = 9
Answer:
Addition Property of Equality
Step-by-step explanation:
So we had:
And then we got:
We did this by adding 2 to both sides of the equation. When we added 2, the left side cancelled and the right side equated to 9:
Since we added 2 to both sides, this is an example of the addition property of equality.
They are not in proportion, since its 6:9 round it down (2:3) so pretend the 6 are apples and the 9 are oranges
Every 2 apples there are 3 oranges
So having 9 apples what is that?
2 x ? = 9
2 x 4.5 = 9
So if you want to keep 2:3 you have you times the oranges by 4.5 aswell!
3 x 4.5 = 13.5
So since it is 9:12 not 9:13.5 they are not in proportion
