95% of red lights last between 2.5 and 3.5 minutes.
<u>Step-by-step explanation:</u>
In this case,
- The mean M is 3 and
- The standard deviation SD is given as 0.25
Assume the bell shaped graph of normal distribution,
The center of the graph is mean which is 3 minutes.
We move one space to the right side of mean ⇒ M + SD
⇒ 3+0.25 = 3.25 minutes.
Again we move one more space to the right of mean ⇒ M + 2SD
⇒ 3 + (0.25×2) = 3.5 minutes.
Similarly,
Move one space to the left side of mean ⇒ M - SD
⇒ 3-0.25 = 2.75 minutes.
Again we move one more space to the left of mean ⇒ M - 2SD
⇒ 3 - (0.25×2) =2.5 minutes.
The questions asks to approximately what percent of red lights last between 2.5 and 3.5 minutes.
Notice 2.5 and 3.5 fall within 2 standard deviations, and that 95% of the data is within 2 standard deviations. (Refer to bell-shaped graph)
Therefore, the percent of red lights that last between 2.5 and 3.5 minutes is 95%
Answer:
Solutions are -10 and 26
Step-by-step explanation:
( - the abolute sign I'm using
( x - 8 ) + 2 = 20
( x - 8 ) = 18
x - 8 = 18 (postive case)
x - 8 + 8 = 18 + 8
x = 26
( x - 8 ) = 18
x - 8 = -18 (negative case)
x - 8 + 8 = -18 + 8
x = -10
Slope of the line that passes through the two point is -2/7
17/51=8/x <-- Cross multiply
17x=408 <-- Divide 17 by both sides
x=24
The shortest side is 24 or B.
The answer would be x + x + 2 = 72. Combine like terms so that 2x + 2 = 72. 2x = 70 and x = 35.
