Answer: 68
Step-by-step explanation:
Formula for sample size when prior estimate of population proportion (p) is available: 
, where z*= critical-value.
E= Margin of error.
Let p be the population proportion of trees are infected with the citrus red mite.
As per given , we have

E= ± 0.08
The critical z-value corresponding to 90% confidence level = z*=1.645
Substitute all the values in the above formula , we get
Required sample size :

[Rounded to next integer.]
Thus, the minimum sample size should be taken =68
-6x is the answer hope it helps
Answer:
I came up with -12
Step-by-step explanation:
8 workers = 6 days to complete
x workers = 4 days faster to complete
6/4=1.5 days faster
1.5 x 8 = 12 workers needed to complete the wall in fours days
Answer:
x = 15°
Step-by-step explanation:
Complementary angles are two angles whose sum = 90°
∠A + ∠B = 90°
3x + 45 = 90
3x = 45
x = 45/3
x = 15°