Answer:
Step-by-step explanation:
To solve this, we are going to make an age table:
Age Now Age 10 years ago
Tanya
Elliot
Filling the in the Age Now column comes from the first sentence. If Elliot is 2 times Tanya's age and we don't know Tanya's age, then Tanya's age is x and Elliot's age is 2x:
Age Now Age 10 years ago
Tanya x
Elliot 2x
Filling in the Age 10 years ago column simply requires that we take their ages in the Age Now column and subtract 10 from each age:
Age Now Age 10 years ago
Tanya x x - 10
Elliot 2x 2x - 10
Since the question is How old is Elliot now based on the fact that 10 years ago....blah, blah, blah, we are using the ages in the 10 years ago column to write our equation. It says:
10 years ago, Elliot was 4 times as old as Tanya. Translated into mathspeak:
2x - 10 = 4(x - 10) and
2x - 10 = 4x - 40 and
-2x = -30 so
x = 15. That means that Elliot is 30 and Tanya is 15
Answer:
The 99% confidence interval for the population proportion of employed individuals who work at home at least once per week is between (0.104, 0.224).
Step-by-step explanation:
In a sample with a number n of people surveyed with a probability of a success of 
, and a confidence level of 
, we have the following confidence interval of proportions.
In which
z is the zscore that has a pvalue of 
.
For this problem, we have that:
99% confidence level
So 
, z is the value of Z that has a pvalue of 
, so 
.
The lower limit of this interval is:
The upper limit of this interval is:
The 99% confidence interval for the population proportion of employed individuals who work at home at least once per week is between (0.104, 0.224).
Answer:
(x+3)(x+7)
Step-by-step explanation:
3 and 7 are factors of 21, and they add up to 10.
