A certain mountain has an elevation of 19,570 feet.

Question

In 1904, the glacier on this peak covered 10 acres. By 2000 this glacier had melted to only 1 acre.

(a) Assume that this glacier melted at a constant rate each year find this yearly/acres rate? (Type a integer or a decimal and round to the nearest thousandth

(b) Use the answer to part (a) to write a linear equation that gives the acreage A of this glacier t years past

Answer 1

(b)  A = - (9/96)t + 10  or  A = - 0.094 · t + 10
                             ↓ 
                    the initial acreage   

Answer 2

In 96 years total loss is 9 acres.  Therefore yearly loss= 9/96 Acres/year =  0.09375 acres/year

If  Loss of acreage is L in time "t"  years, then L= 0.09375t. 

So the Equation is A= A0 - 0.09375t where A0 is the initial acreage and A is the acreage after "t" years.