Finding the Third Proportional to 638,138 and 987,977.50

Step by Step Solution

1. Step 1: Write the proportion equation
   638,138 : 987,977.50 = 987,977.50 : x
2. Step 2: Convert to fraction form
   638,138/987,977.50 = 987,977.50/x
3. Step 3: Cross multiply
   638,138x = 987,977.50 × 987,977.50
4. Step 4: Simplify right side
   638,138x = 976,099,540,506.25
5. Step 5: Solve for x
   x = 976,099,540,506.25/638,138
6. Step 6: Final answer
   x = 1,529,605.73