First of all, the section does not apply to the calculations for the answer. It's just extraneous (irrelevant) data.
Second: work out process
We need to add the two fields' yield. Since both are in the same units (<u>tons</u>), we're going to just add them as is. So that'd be
<em>The denominators don't match!</em> So we're going to have to convert the fraction parts to match. But we can add the whole numbers since they don't affect the denominator value:
So now we have to find the LCD, least common denominator, for these two fractions. Which would be here, so...
Third: fraction conversion
First part → 5 times 12 = 60, so the first fraction will be converted as
Second part → 12 times 5 = 60, so the second fraction will now be converted as