Answer:
30 i think
Step-by-step explanation:
For 12, you would do 90=4x+42, and 48=4x, and x=12
for 15, you would do 90=8x+66, and 24=8x, and x=3
for 18, you would do 90=3x+57, and 33=3x, and x=11
The study has the smallest margin of error for a 98% confidence interval is <span>The northern California study with a margin of error of 3.2%.
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