2b: If x is 2.1, then one side of the rectangle is 2.1, and another is 2.1*5=10.5. Thus, the perimeter is 2*(2.1+10.5)=2*12.6=25.2.
3: One side of the square with side-length three will not be on the outside, so we have 3*3=9 inches perimeter from the square of side-length 3. The square of side-length 6 has 3 from the top side missing from the outer perimeter, because it coincides with a side of the square of side-length three. This square contributes 6*4-3=33 inches. The total perimeter is 33+9=42 inches.
Hope this can help you ^_^
Answer: 90% of people getting married for the first time get married before age of 31.13.
Step-by-step explanation:
Given : The average age (
) for a person getting married for the first time is 26 years (U.S. News and World Report, June 6, 1994).
We assume that the ages for first marriages have a normal distribution with a standard deviation (
) of 4 years.
Let x be the age before that 90% of people getting married for the first time get married.
From z-table , the value corresponds to p-value of 0.90 is 1.28155.
Formula : 

Hence, 90% of people getting married for the first time get married before age of 31.13.
Answer:
x = 15
Step-by-step explanation:
Create the proportion: 5/7 = x/21
Multiply both sides by 21: 15 = x