Finding the Fourth Proportional to 105,164.96, 145,131 and 57,420.80

Step by Step Solution

1. Step 1: Write the proportion equation
   105,164.96 : 145,131 = 57,420.80 : x
2. Step 2: Convert to fraction form
   105,164.96/145,131 = 57,420.80/x
3. Step 3: Cross multiply
   105,164.96x = 145,131 × 57,420.80
4. Step 4: Simplify right side
   105,164.96x = 8,333,538,124.80
5. Step 5: Solve for x
   x = 8,333,538,124.80/105,164.96
6. Step 6: Final answer
   x = 79,242.54