Suppose a polling agency reported that 45.7% of registered voters were in favor of raising income taxes to pay down the national
debt. The agency states that results are based on telephone interviews with a random sample of 1033 registered voters. Suppose the agency states the margin of error for 99% confidence is 4.0%. Determine and interpret the confidence interval for the proportion of registered voters who are in favor of raising income taxes to pay down the national debt.
99% confidence interval for the proportion of registered voters who are in favor of raising income taxes to pay down the national debt. = (0.417, 0.497)
Interpretation : We are 99% sure that the true population proportion of registered voters who are in favor of raising income taxes to pay down the national debt lies in interval (0.417, 0.497).
<em>A) The reference angle should be </em><u><em>,</em></u><em> and the sign of the value should be </em><u><em>negative.</em></u>
Step-by-step explanation:
cos()
Remove full rotations of 2π until the angle is between 0 and 2.
cos()
Apply the reference angle by finding the angle with equivalent trig values in the first quadrant. Make the expression negative because cosine is negative in the third quadrant.