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%
Rational expressions are multiplied and divided the same way numeric fractions are.
- 30m^2 - 10m + 30
distribute your negative 10, you will first get 30m, then - 30m^2.
next distribute the negative 5, you will get - 40m, then 30.
combine like terms, and make sure its in standard form, - 30m^2 - 10m + 30
1 foot<span> = </span>12<span> inches
</span>864/12=72 T<span>he window is 72 square feet.
A man uses </span>8 pieces of glass per square foot to make a stained glass window. So he needs to use 72*8=576 <span>pieces of glass.</span>
The answer would be 230 2/3, because to get the perimeter you have to add all the sides together, 60 5/6 + 59 1/3 + 56 1/6 + 54 1/3 = 230 2/3
