The greatest common factor (GCF) is the greatest factor that divides two integers.

The factors of a number are all positive integers that divide evenly into the number. The factors of 20 are 1, 2, 4, 5, 10, 20.

To subtract 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:

\( \frac{4 x 3}{2 x 3} \) - \( \frac{8 x 1}{6 x 1} \)

\( \frac{12}{6} \) - \( \frac{8}{6} \)

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

\( \frac{12 - 8}{6} \) = \( \frac{4}{6} \) = \(\frac{2}{3}\)

To add these radicals together their radicands must be the same:

3\( \sqrt{50} \) + 9\( \sqrt{2} \)
3\( \sqrt{25 \times 2} \) + 9\( \sqrt{2} \)
3\( \sqrt{5^2 \times 2} \) + 9\( \sqrt{2} \)
(3)(5)\( \sqrt{2} \) + 9\( \sqrt{2} \)
15\( \sqrt{2} \) + 9\( \sqrt{2} \)

Now that the radicands are identical, you can add them together:

By buying two shirts, Ezra will save $44 x \( \frac{15}{100} \) = \( \frac{$44 x 15}{100} \) = \( \frac{$660}{100} \) = $6.60 on the second shirt.

So, his total cost will be
$44.00 + ($44.00 - $6.60)
$44.00 + $37.40
$81.40