Dividing fractions is just about as easy; there's just one extra step. When you divide by a fraction, the first thing you do is flip-n-multiply. That is, you take the second fraction, flip it upside-down (find the reciprocal), and multiply the first fraction by this flipped fraction.1  Simplify. 2  Simplify.ultiplying fractions is easy: you multiply the top numbers and multiply the bottom numbers. For instance: When possible, you reduce. In the example above, however, nothing reduces, because 8 and 45 have no factors in common.
Sodium phosphate tablets are prescribed by the doctor doing the colonoscopy. There are two different brands, depending on which your doctor prescribes -- Visicol, a 40-tablet regimen, and Osmo-Prep, a 32-tablet regimen.
In Osmo-Prep (the newer form), the tablets are taken the evening before and the morning of the colonoscopy. The evening before the test, 4 tablets are taken with 8 ounces of a clear liquid every 15 minutes for a total of 5 doses (20 tablets total).