Answer:
So we use the t-distribution to compute a confidence interval for the average age of people using online dating services
Step-by-step explanation:
Confidence interval for a mean.
We have to decide between the t-distribution and the z-distribution.
T-distribution: We use the sample standard deviation.
Z-distribution: We use the population standard deviation.
In this problem:
The average age of those that were using online dating services was 35 years old with a sample standard deviation of 12 years.
So we use the t-distribution to compute a confidence interval for the average age of people using online dating services
297 because 289 rounds to 290 plus 7 is 297
Answer:
x = 20
Step-by-step explanation:
x° + 2x° + (x+10)° = 90°
3x° + x° + 10° = 90°
4x° + 10° = 90°
4x° = 90°-10°
4x° = 80°
x = 80/4
x = 20
