Answer:
A)

B)

C)

Explanation:
Part A)
The Hendersons were traveling 1/3 of the distance on the first day.
However, they had to stop, having only traveled 1/4 of the 1/3 distance.
So, we can multiply the two fractions together.
Therefore, the fraction of the total distance they traveled is given by:

The Hendersons traveled 1/12 of the total distance.
Part B)
We are assuming the bottle of milk was full at the beginning.
So, at the beginning, there were 1/1 bottle of milk left.
Howie fed a piglet 1/5 of the bottle. So, there is now:

Of the bottle left.
Making common denominators and subtracting yields:

So, after feeding the piglet, 4/5 of the bottle of milk was still there.
3/4 of the remainder was fed to a calf.
So, the amount that was fed to the calf is 3/4 times 4/5. Therefore:

Multiply:

So, the calf drank 3/5 of the bottle of milk.
Part C)
Nathan used 2 (5/6) loaves of bread to make 4 sandwiches.
First, convert 2 (5/6) to an improper fraction. So:

Nathan made 4 sandwiches using this. So, we will divide this by 4. Note that this is the same as multiplying by 1/4. Therefore:

So, Nathan used 17/24 loaves of bread per sandwich.