Final answer:
Faris and Ahmed painted (5/12) and (4/12) of a fence respectively. Adding these fractions, they painted a total of 9/12, which simplifies to 3/4 of the fence.
Step-by-step explanation:
To determine how much of the fence Faris and Ahmed painted altogether, you need to add the fractions that represent the parts of the fence they painted individually. Faris painted (5/12) of the fence and Ahmed painted (4/12) of the fence. When you add these two fractions together, making sure that the denominators are the same, you get:
(5/12) + (4/12) = (5 + 4)/12 = 9/12
To simplify the fraction, you divide both the numerator and the denominator by their greatest common divisor, which is 3. Therefore, 9/12 simplifies to:
9 ÷ 3 / 12 ÷ 3 = 3/4
So, Faris and Ahmed painted three-quarters of the fence altogether.