Finding the Fourth Proportional to 105,420.96, 145,480.59 and 57,673.89

Step by Step Solution

1. Step 1: Write the proportion equation
   105,420.96 : 145,480.59 = 57,673.89 : x
2. Step 2: Convert to fraction form
   105,420.96/145,480.59 = 57,673.89/x
3. Step 3: Cross multiply
   105,420.96x = 145,480.59 × 57,673.89
4. Step 4: Simplify right side
   105,420.96x = 8,390,431,544.80
5. Step 5: Solve for x
   x = 8,390,431,544.80/105,420.96
6. Step 6: Final answer
   x = 79,589.79