Answer:
2 proportions z test
The two populations are named as residents from the first county and residents from the second county.
Step-by-step explanation:
This is testing hypothesis about the difference between two proportions.
When the proportions are tested if they are the test statistic
z= ( p^1-p^2)- (p1-p2) / √p₁q₁/n₁ + p₂q₂/ n₂
where p^1 is the proportion of success in the first sample and p^2 of size n₁ is the proportion of success in the second sample of size n₂ with unknown proportions of successes p1 and p2 respectively.
When the sample sizes are sufficiently large
z= ( p^1-p^2)- (p1-p2) / √p₁q₁/n₁ + p₂q₂/ n₂ is approximately standard normal.
The two populations are named as residents from the first county and residents from the second county.
Step-by-step explanation:
x = number of novels
y = number of dictionaries
x = 8y
88x + 208y = 13680
now, using the identity of the first equation in the second equation gives us
88(8y) + 208y = 13680
704y + 208y = 13680
912y = 13680
y = 13680/912 = 15
x = 8y = 8×15 = 120
so, there were 120 novels and 15 dictionaries sold.
Answer: ok what is it
Step-by-step explanation: