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:
-j, 0, j-k
Step-by-step explanation:
j is a positive number, so -j will be less than 0.
j is a number greater than k, so j - k will be greater than 0.
From least to greatest, the order is ...
-j, 0, j-k
Answer:
the second one +1.5 m/s
Step-by-step explanation:
to find the velocity you need to find the slope of the two points then just put it into the time (s) and position (m) terms which equals +1.5 m/s
Answer:
24: x = 31
25: x = 15
Step-by-step explanation:
Remark
24 is supplementary which means that the two angles add to 180o which is on the right hand side of the equation
25 is complementary which means that the two angles add to 90o which is on the left hand side of the equation
Twenty Four
3x + 31 +2x - 6 = 180 Collect the like terms
3x +2x + 31 - 6 = 180 Do the adding and subtracting.
5x + 25 = 180 Subtract 25 from both sides
5x + 25 - 25 = 180 - 25
5x = 155 Divide by 5
x = 155/5
x = 31
Check
3x + 31 = 3*31 + 31
3x + 31 = 93 + 31
3x + 31 = 124
2x - 6 = 2*31 - 6 = 62 - 6 = 56
Total 124 + 56 = 180 as it should.
Twenty Five
Equation
3x+ 4x - 15 = 90
Solution
7x - 15 = 90 Like terms have been collected on the left.
7x = 90 + 15 15 was added to both sides
7x = 105 Divide by 7
x = 15 I'll leave the check to you
