Finding the Third Proportional to 128,787.56 and 189,322.50

Step by Step Solution

1. Step 1: Write the proportion equation
   128,787.56 : 189,322.50 = 189,322.50 : x
2. Step 2: Convert to fraction form
   128,787.56/189,322.50 = 189,322.50/x
3. Step 3: Cross multiply
   128,787.56x = 189,322.50 × 189,322.50
4. Step 4: Simplify right side
   128,787.56x = 35,843,009,006.25
5. Step 5: Solve for x
   x = 35,843,009,006.25/128,787.56
6. Step 6: Final answer
   x = 278,311.11