# Five sets and a movie director

The letters A to E and the numbers 1 to 7 are according to an order.
What are the sets A, B, C, D and E?

A = {1, 3, 4, 7}
B = {2, 3, 4, 6}
C = {1, 2, 7}
D = {5}
E = {1, 3, 6}

The clues for numbers 1 to 7 are as given below.
Which name fills the blank?

1. An Australian singer-songwriter
2. The second part of a certain country's name
3. A plant genus
4. A plant genus
5. The International Cat Association
6. A 1948 movie directed by _________
7. A variant of Leah or Lea

Hint

Think of two separate lists that are 5 and 7 in number

1. An Australian singer-songwriter = SIA
2. The second part of a certain country's name = RICA (Costa Rica)
3. A plant genus = ERICA
4. A plant genus = ERICA (again)
5. The International Cat Association = TICA (its acronym)
6. A 1948 movie directed by _________ = (to be solved shortly...)
7. A variant of Leah or Lea = LIA

What are these? They are the:

endings of the names of continents:

ASIA, AFRICA, NORTH AMERICA, SOUTH AMERICA, ANTARCTICA, ..., AUSTRALIA (in place of 'Oceania').

This means clue 6 must in some way indicate the missing one, and this can be done if it reads:

6. A 1948 movie directed by ALFRED HITCHCOCK = ROPE

...since this is the tail end of the missing continent, EUROPE.

Returning to our 5 sets, what are these? Substitute what the 7 answers represent into their sets to get...

...groups of continents. And how are they grouped? In terms of the oceans that they border:

A = {ASIA, NORTH AMERICA, SOUTH AMERICA, AUSTRALIA} = PACIFIC
B = {AFRICA, NORTH AMERICA, SOUTH AMERICA, EUROPE} = ATLANTIC
C = {ASIA, AFRICA, AUSTRALIA} = INDIAN
D = {ANTARCTICA} = SOUTHERN
E = {ASIA, NORTH AMERICA, EUROPE} = ARCTIC

As confirmation, notice that the two lists are complete and ranked in order.

i.e. There are precisely 7 continents and 5 oceans on Earth, and both the continents and oceans are listed in order of decreasing size.

One final note:

In my original solution I had 'South AFRICA' as a legitimate solution to #2; however, as @Marius points out in comments, 'Costa RICA' also works here, and is much more satisfying since it does not give the entire name of the continent all at once.

• (For the record, before the hint I had already solved the 7 but not the 5. The hint pushed me to think in the right direction for the latter part...)
– Stiv
Aug 24, 2022 at 23:18
• There are still a lot of us old fogeys that refuse to accept that D exists. Aug 25, 2022 at 0:32
• nice deduction. I have a suggestion if you don't mind. I think for #2, Costa Rica fits better. As it discloses only the suffix as for the rest of the numbers. Aug 25, 2022 at 12:40
• @Marius I like that suggestion a lot - nice thinking :)
– Stiv
Aug 25, 2022 at 12:42