Finding the Fourth Proportional to 105,141.48, 145,097.28 and 57,399

Step by Step Solution

1. Step 1: Write the proportion equation
   105,141.48 : 145,097.28 = 57,399 : x
2. Step 2: Convert to fraction form
   105,141.48/145,097.28 = 57,399/x
3. Step 3: Cross multiply
   105,141.48x = 145,097.28 × 57,399
4. Step 4: Simplify right side
   105,141.48x = 8,328,438,774.72
5. Step 5: Solve for x
   x = 8,328,438,774.72/105,141.48
6. Step 6: Final answer
   x = 79,211.73