1. Yes , Yes
2. Yes , Yes
3. No , No
4. No, Yes
Answer:


So then we can conclude that we expect the middle 95% of the values within 18 and 30 minutes for this case
Step-by-step explanation:
For this case we can define the random variable X as the amount of time it takes her to arrive to work and we know that the distribution for X is given by:

And we want to use the empirical rule to estimate the middle 95% of her commute times. And the empirical rule states that we have 68% of the values within one deviation from the mean, 95% of the values within two deviations from the mean and 99.7 % of the values within 3 deviations from the mean. And we can find the limits on this way:


So then we can conclude that we expect the middle 95% of the values within 18 and 30 minutes for this case
Answer:
21
Step-by-step explanation:
y+9 = ?
y=12
12+9=21
2x+3=7
2x+3-3=7-3
Whenever moving a number to the other side you have to change the sign .
2x= 4
x=2