Finding the Fourth Proportional to 91,714.30, 128,487.50 and 91,714.30

Step by Step Solution

1. Step 1: Write the proportion equation
   91,714.30 : 128,487.50 = 91,714.30 : x
2. Step 2: Convert to fraction form
   91,714.30/128,487.50 = 91,714.30/x
3. Step 3: Cross multiply
   91,714.30x = 128,487.50 × 91,714.30
4. Step 4: Simplify right side
   91,714.30x = 11,784,141,121.25
5. Step 5: Solve for x
   x = 11,784,141,121.25/91,714.30
6. Step 6: Final answer
   x = 128,487.50