Question

You are testing a new sugar replacement that you think is indigestible (and potentially useful in diet products). You feed 1 gram of the purifiied product to each of 5 rats, then collect feces for the following 48 hours, which is expected to be enough time to clear the GI tract. This product is not present in the rats' chow. Based on the results below, what is the % digestibility of this sugar alternative product? Total feces (all 5 rats, 48 hours): 20 grams Concentration of sugar alternative in feces: 22.5% Give your answer in %, but do not include the % sign in your answer.

Answer 1

Answer: The % digestibility of the sugar alternative is 10.

Explanation:

First we have to know how many grams of the sugar replacement were in the total rat feces. We know 22,5% of the feces were the sugar replacement, so we use cross multiplication for that:

If 20 grams is 100% of the feces, then

x grams / 22.5% = 20grams / 100%

xgrams = (22.5 . 20grams) / 100% = 4.5grams

If each rat ingested 1gram of the sugar replacement, all five rats ate a total of 5grams.

Now we have to check how much of this sugar replacement was digested. If the rats ate 5grams and 4.5grams were present in their feces

5grams - 4.5grams = 0.5grams

This means they digested 0.5grams.

We use cross multiplication again to find out which percentage of the initial sugar replacement this represents.

If 5grams is 100% of the ingested sugar replacement, then

x% / 0.5grams = 100% / 5grams

x% = (0.5grams . 100%) / 5grams = 10%