Answer:
The American population was 20% of the British population.
Step-by-step explanation:
Let us call
the american population,
the British population before the migration, and
the population that migrated from America to Britannia.
Now, the population
that migrated was 20% of the american population:
,
and the same population
increase the British population by 4%:

Combining equation (1) and (2) we get:



Thus, the American population was 20% of the British population.
Answer:
The answer is 16 I've seen this before so I would know. and your welcome
Step-by-step explanation:
P=2(l + b)
P=2l + 2b
P-2b=2l
P-2b/2=l
C is your answer