Answer:
97.6% of the trees will have diameters between 7.6 and 18.6 inches.
Step-by-step explanation:
We are given the following information in the question:
Mean, μ = 12 inches
Standard Deviation, σ = 2.2 inches
We are given that the distribution of diameter of tree is a mound shaped distribution that is a normal distribution.
Formula:

P(diameters between 7.6 and 18.6 inches)

97.6% of the trees will have diameters between 7.6 and 18.6 inches.
Answer:
1) 20% change I think its an increase.
If needed I could try to answer the 2nd question but I am sure that I got the first one right.
Step-by-step explanation:
Answer:
1
Step-by-step explanation:
Answer:
the diameter is 6 units
Step-by-step explanation:
3×2=6
Answer:
3000 text messages can be sent without breaking the budget.
Step-by-step explanation:
Since each month your cell phone company charges $ 50 for your plan plus 3 cents for each text you send, and you have $ 140 budgeted for cell phone expenses for the month, to make a determination about the number of texts you can send each month the following calculation must be performed:
(140 - 50) / 0.03 = X
90 / 0.03 = X
3000 = X
Therefore, 3000 text messages can be sent without breaking the budget.