By buying two shirts, Frank will save $28 x \( \frac{20}{100} \) = \( \frac{$28 x 20}{100} \) = \( \frac{$560}{100} \) = $5.60 on the second shirt.

To add these fractions, first find the lowest common multiple of their denominators. The first few multiples of 2 are [2, 4, 6, 8, 10, 12, 14, 16, 18, 20] and the first few multiples of 6 are [6, 12, 18, 24, 30, 36, 42, 48, 54, 60]. The first few multiples they share are [6, 12, 18, 24, 30] making 6 the smallest multiple 2 and 6 share.

Next, convert the fractions so each denominator equals the lowest common multiple:

\( \frac{7 x 3}{2 x 3} \) + \( \frac{9 x 1}{6 x 1} \)

\( \frac{21}{6} \) + \( \frac{9}{6} \)

Now, because the fractions share a common denominator, you can add them:

\( \frac{21 + 9}{6} \) = \( \frac{30}{6} \) = 5

If 81% of the town's 24,000 voters cast ballots the number of votes cast is:

(\( \frac{81}{100} \)) x 24,000 = \( \frac{1,944,000}{100} \) = 19,440

The mayor got 78% of the votes cast which is:

(\( \frac{78}{100} \)) x 19,440 = \( \frac{1,516,320}{100} \) = 15,163 votes.

By buying two shirts, Frank will save $35 x \( \frac{40}{100} \) = \( \frac{$35 x 40}{100} \) = \( \frac{$1400}{100} \) = $14.00 on the second shirt.

So, his total cost will be
$35.00 + ($35.00 - $14.00)
$35.00 + $21.00
$56.00

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