Finding the Fourth Proportional to 91,748.60, 128,185.60 and 91,748.60

Step by Step Solution

1. Step 1: Write the proportion equation
   91,748.60 : 128,185.60 = 91,748.60 : x
2. Step 2: Convert to fraction form
   91,748.60/128,185.60 = 91,748.60/x
3. Step 3: Cross multiply
   91,748.60x = 128,185.60 × 91,748.60
4. Step 4: Simplify right side
   91,748.60x = 11,760,849,340.16
5. Step 5: Solve for x
   x = 11,760,849,340.16/91,748.60
6. Step 6: Final answer
   x = 128,185.60