Answer:
250
Explanation:
The general term of a geometric sequence has the form:
an= a⋅r^n−1
where a is the initial term and r the common ratio.
In the example: a 1 = 1250 and 3 = 50
So: r^2 = ar^2/ar^0 = a^3/a^1 = 50/1250=1/25=1/5^2
Hence: r = ± 1/5
Then: a^2= a⋅ r ^2−1 = 1250⋅(±1/5)= ±250
