To find the year in which the number of medical doctors reached 860,000, we need to substitute the value of D into the equation and solve for t.
Let's substitute D = 860 into the equation:
860 = 431.61 + 121.8t
Now, let's solve for t:
121.8t = 860 - 431.61
121.8t = 428.39
t = 428.39 / 121.8
t ≈ 3.52
Since t represents the year, with t = 8 corresponding to 1998, we need to add 8 to t:
Year = 8 + 3.52
Year ≈ 11.52
So, in approximately the 11th month of the year following 1998, which is 1998 + 11 = 2009, the number of medical doctors reached 860,000.
To predict in which year the number of medical doctors will reach 1,010,000, we can use the same equation:
D = 431.61 + 121.8t
Let's substitute D = 1,010,000 into the equation:
1,010,000 = 431.61 + 121.8t
Now, let's solve for t:
121.8t = 1,010,000 - 431.61
121.8t = 1,009,568.39
t = 1,009,568.39 / 121.8
t ≈ 8.29
Again, since t represents the year, with t = 8 corresponding to 1998, we add 8 to t:
Year = 8 + 8.29
Year ≈ 16.29
So, in approximately the 16th month of the year following 1998, which is 1998 + 16 = 2014, the number of medical doctors is predicted to reach 1,010,000.