Answer:
- P(x < 84) = 0.3085 or approximately 31%
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<em>Hello to you from Brainly team!</em>
<h3>Given</h3>
- Mean grade μ = 86,
- Standard deviation σ = 4,
- Grade limit x = 84.
<h3>To find </h3>
- Probability of that a randomly selected grade is less than 84 or P(x < 84).
<h3>Solution</h3>
Find z-score using relevant equation:
Substitute values and calculate:
Using the z-score table find the corresponding P- value.
- P(x < 84) = 0.30854 or approximately 31%
Answer:1.17
Step-by-step explanation:
Answer:
Part A) x = -3
Part B) x = 1, x = -7
Part C) x < -7
Part D) 2
Step-by-step explanation:
<h3>Part A)</h3>
2(x - 3) = 3x - 3
<em>open the parenthesis</em>
2 * x - 2 * 3 = 3x - 3
2x - 6 = 3x - 3
<em>subtract 2x from both sides</em>
2x - 2x - 6 = 3x - 2x - 3
-6 = x - 3
<em>add 3 to both sides</em>
-6 + 3 = x
-3 = x
<h3>
Part B)</h3>
|2x + 6| = 8
<em>split this into two equations:</em>
<em>2x + 6 = 8</em>
<em>&</em>
<em>2x + 6 = -8</em>
2x + 6 = 8
2x = 8-6
2x = 2
x = 1
2x + 6 = -8
2x = -8 - 6
2x = -14
x = -7
<h3>Part C)</h3>
-5(x + 1) > 30
<em>open the parenthesis</em>
-5x - 5 > 30
<em>add 5 to both sides</em>
-5x > 35
<em>divide both sides by -5</em>
x > -7
<em>since you divided by a negative, flip the sign.</em>
x < -7
<h3>
Part D)</h3>
f(x) = 4x - 3
<em>substitute x for 5</em>
5 = 4x - 3
5 + 3 = 4x
8 = 4x
2 = x
Using the <em>system of equation</em> created, Emily will catch up Lucy after 30 seconds
Given the Parameters :
- Lucy's distance = 2t
- Emily's distance = 5t
<u>We can set up an equation to represent the required scenario thus</u> :
Emily's distance = Lucy's distance + 90
5t = 2t + 90
We solve for t
<em>Collect like terms</em> :
5t - 2t = 90
3t = 90
Divide both sides by 3 to isolate t
t = 90/3
t = 30
Therefore, Emily will catch up with Lucy after 30 seconds
Learn more :brainly.com/question/13218948
