Answer: 0.8238
Step-by-step explanation:
Given : Scores on a certain intelligence test for children between ages 13 and 15 years are approximately normally distributed with 
and 
.
Let x denotes the scores on a certain intelligence test for children between ages 13 and 15 years.
Then, the proportion of children aged 13 to 15 years old have scores on this test above 92 will be :-
![P(x>92)=1-P(x\leq92)\\\\=1-P(\dfrac{x-\mu}{\sigma}\leq\dfrac{92-106}{15})\\\\=1-P(z\leq })\\\\=1-P(z\leq-0.93)=1-(1-P(z\leq0.93))\ \ [\because\ P(Z\leq -z)=1-P(Z\leq z)]\\\\=P(z\leq0.93)=0.8238\ \ [\text{By using z-value table.}]](https://tex.z-dn.net/?f=P%28x%3E92%29%3D1-P%28x%5Cleq92%29%5C%5C%5C%5C%3D1-P%28%5Cdfrac%7Bx-%5Cmu%7D%7B%5Csigma%7D%5Cleq%5Cdfrac%7B92-106%7D%7B15%7D%29%5C%5C%5C%5C%3D1-P%28z%5Cleq%20%7D%29%5C%5C%5C%5C%3D1-P%28z%5Cleq-0.93%29%3D1-%281-P%28z%5Cleq0.93%29%29%5C%20%5C%20%5B%5Cbecause%5C%20P%28Z%5Cleq%20-z%29%3D1-P%28Z%5Cleq%20z%29%5D%5C%5C%5C%5C%3DP%28z%5Cleq0.93%29%3D0.8238%5C%20%5C%20%5B%5Ctext%7BBy%20using%20z-value%20table.%7D%5D)
Hence, the proportion of children aged 13 to 15 years old have scores on this test above 92 = 0.8238
Answer:
1 hour = 10/x
Step-by-step explanation:
Example: the man walks 10 miles in 5 hours. How many in 1 hour: 10/5= 2 miles
Answer:
36 ft
Step-by-step explanation:
Daniela facing a 12 ft tall statue that is 15 ft away. She can see the reflection of the top of the statue in a puddle on the ground 5 ft in front of her. How tall is Daniela?
Hence, this is calculated as:
5ft/15ft = 12 ft/Daniela's height
Cross Multiply
5ft × Daniela's height = 15ft × 12ft
Daniela's height = 15ft × 12 ft/5ft
= 36ft
Therefore, Daniela's height = 36 ft
Answer:
X = -5
Step-by-step explanation:
-6x + 18 = 7 - (4x + 9)
first we simplify the parentheses.
distribute the invisible number one created by the negative sign in front of the parentheses to get -6x + 18 = 7 - 4x - 9
then simplify further by subtracting 9 from the right side, leaving you with
-6x + 18 = -2 - 4x
next, add 2 to both sides to isolate the variable.
-6x + 20 = -4x
then, to isolate the variable further add 6x to both sides.
20 = -4x
divide both sides by -4 to isolate the variable
-5 = x
so, x = -5
Answer:
5/6
Step-by-step explanation:
brainliest please
