Finding the Fourth Proportional to 102,499.40, 141,435.02 and 57,172.07

Step by Step Solution

1. Step 1: Write the proportion equation
   102,499.40 : 141,435.02 = 57,172.07 : x
2. Step 2: Convert to fraction form
   102,499.40/141,435.02 = 57,172.07/x
3. Step 3: Cross multiply
   102,499.40x = 141,435.02 × 57,172.07
4. Step 4: Simplify right side
   102,499.40x = 8,086,131,870.86
5. Step 5: Solve for x
   x = 8,086,131,870.86/102,499.40
6. Step 6: Final answer
   x = 78,889.56