Answer:
The number of trees at the begging of the 4-year period was 2560.
Step-by-step explanation:
Let’s say that x is number of trees at the begging of the first year, we know that for four years the number of trees were incised by 1/4 of the number of trees of the preceding year, so at the end of the first year the number of trees was, and for the next three years we have that
Start End
Second year --------------
Third year -------------
Fourth year --------------
So the formula to calculate the number of trees in the fourth year is
we know that all of the trees thrived and there were 6250 at the end of 4 year period, then
⇒
Therefore the number of trees at the begging of the 4-year period was 2560.
