Answer: A point estimate for the proportion of adults aged 18 or older who feel there is too little spending on national defense is 0.3.
Explanation:
Given : In a poll , the sample size of adults aged 18 or older : n=1040
Out of them , the number of persons stated that they believe there is too little spending on national defense: x= 18
Let p be the proportion of adults aged 18 or older who feel there is too little spending on national defense.
Now , as per sample , the sample proportion of adults aged 18 or older who feel there is too little spending on national defense would be :
Since , the sample proportion is the best estimate of the population proportion.
Therefore, a point estimate for the proportion of adults aged 18 or older who feel there is too little spending on national defense is 0.3.