Finding the Fourth Proportional to 105,113, 145,059 and 57,369.40

Step by Step Solution

1. Step 1: Write the proportion equation
   105,113 : 145,059 = 57,369.40 : x
2. Step 2: Convert to fraction form
   105,113/145,059 = 57,369.40/x
3. Step 3: Cross multiply
   105,113x = 145,059 × 57,369.40
4. Step 4: Simplify right side
   105,113x = 8,321,947,794.60
5. Step 5: Solve for x
   x = 8,321,947,794.60/105,113
6. Step 6: Final answer
   x = 79,171.44