Finding the Third Proportional to 87,122.25 and 128,131.50

Step by Step Solution

1. Step 1: Write the proportion equation
   87,122.25 : 128,131.50 = 128,131.50 : x
2. Step 2: Convert to fraction form
   87,122.25/128,131.50 = 128,131.50/x
3. Step 3: Cross multiply
   87,122.25x = 128,131.50 × 128,131.50
4. Step 4: Simplify right side
   87,122.25x = 16,417,681,292.25
5. Step 5: Solve for x
   x = 16,417,681,292.25/87,122.25
6. Step 6: Final answer
   x = 188,444.18