what is the difference in which each question is asking, because the answers are derived in different methods and why

An Echo has 300 litres of fuel on board at start up.

The flight fuel required is 120 litres.
The fixed reserve is 15 gallons.
The start up allowance is 3 gallons.
Fuel flow for holding is 17.2 gph.

The maximum time the aircraft could plan to hold at the destination aerodrome is -

Select one:
105 min
75 min
86 min
95 min

AND

An Echo aeroplane is to conduct a search for a missing boat.

Given that -

Flight fuel required to transit to and from the search area is 30 US gal
Take-off is with 130 US gal
Your operator requires you to allow a variable reserve on all flights
Fuel flow for the search is 17.2 gph
Fixed reserve is 15 gallons

The maximum time that can be spent in the search area is closest to -

Select one:
230 min
300 min
244 min
200 min




Thank You

In both cases you begin by finding the flight fuel available. In the first question, find the flight fuel required and compare it with the flight fuel available. The difference is the margin fuel and it can be used for holding.

In the second question, a search is actually AWK, but the preamble to the questions says that your operator requires all flight to carry the variable reserve, so you treat it as you would CHTR. When you find the flight fuel available, subtract the transit fuel and the rest can be used for holding. They're not different methods.
Bob

Hey Bob, does the 30 gal in the question "to transit and from the search area" mean 30gal total or 30gal each way (totalling 60 gal)? I had a few of these in my exam and was a little confused. Common sense would say total but I can always feel it's a trick.

One other question related to echo loading, I was given:

The aircraft is "loaded for takeoff" as follows: weight 2020 and index unit 450.

Further down in the question they mention the two seats in row 2 seats have been removed.

My questions is: do I then remove the seats myself or does the term "loaded for take off" mean that is the final weight in IU after seat weight adjustments are made.

Thank you