Finding the Fourth Proportional to 105,057.12, 144,978.88 and 57,310.56

Step by Step Solution

1. Step 1: Write the proportion equation
   105,057.12 : 144,978.88 = 57,310.56 : x
2. Step 2: Convert to fraction form
   105,057.12/144,978.88 = 57,310.56/x
3. Step 3: Cross multiply
   105,057.12x = 144,978.88 × 57,310.56
4. Step 4: Simplify right side
   105,057.12x = 8,308,820,800.97
5. Step 5: Solve for x
   x = 8,308,820,800.97/105,057.12
6. Step 6: Final answer
   x = 79,088.60