Advertising campaign

#1
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Before an intensive TV advertising campaign, the producers of Nike athletic shoes find that 29 of a random sample of 200 upper-income adults were aware of their new leisure shoe line. A second random sample of 300 such adults is taken after the campaign. Now 96 of the persons sampled can identify the new line. Give a 99% confidence interval for the increase in the proportion of upper-income adults showing brand awareness.


Here's what I came up with -.27 to -.07 ?