Finding the Fourth Proportional to 91,892,664.30, 128,745,389.40 and 91,892,664.30

Step by Step Solution

1. Step 1: Write the proportion equation
   91,892,664.30 : 128,745,389.40 = 91,892,664.30 : x
2. Step 2: Convert to fraction form
   91,892,664.30/128,745,389.40 = 91,892,664.30/x
3. Step 3: Cross multiply
   91,892,664.30x = 128,745,389.40 × 91,892,664.30
4. Step 4: Simplify right side
   91,892,664.30x = 11,830,756,848,306,978
5. Step 5: Solve for x
   x = 11,830,756,848,306,978/91,892,664.30
6. Step 6: Final answer
   x = 128,745,389.40