A Bipartisan Policy Center article indicated that 57.5% of the voting-age voters cast ballots in the 2012 presidential election. It also indicated that 70% of registered voters voted in the election. The percent of those who voted for President Obama was 51.01%.
a. Determine the proportion of voting-age voters who voted for President Obama.
b. Determine the proportion of voting-age voters who were registered to vote.