Answer:

Step-by-step explanation:
-The margin of error is calculated using the formula:

-We substitute the values, n=900 and ME=30 in the formula to solve for standard deviation:

Hence, the population standard deviation is 547.1125
Answer:
The answer would have came out of 3.84615384615
Then round up the answer to 3.85. So the unit price is $3.85
(3x+8)(3x+8) is the answer :))