Finding the Third Proportional to 117,639 and 256,603.50

Step by Step Solution

1. Step 1: Write the proportion equation
   117,639 : 256,603.50 = 256,603.50 : x
2. Step 2: Convert to fraction form
   117,639/256,603.50 = 256,603.50/x
3. Step 3: Cross multiply
   117,639x = 256,603.50 × 256,603.50
4. Step 4: Simplify right side
   117,639x = 65,845,356,212.25
5. Step 5: Solve for x
   x = 65,845,356,212.25/117,639
6. Step 6: Final answer
   x = 559,723.87