Finding the Fourth Proportional to 78,131.67, 107,821.98 and 42,321.57

Step by Step Solution

1. Step 1: Write the proportion equation
   78,131.67 : 107,821.98 = 42,321.57 : x
2. Step 2: Convert to fraction form
   78,131.67/107,821.98 = 42,321.57/x
3. Step 3: Cross multiply
   78,131.67x = 107,821.98 × 42,321.57
4. Step 4: Simplify right side
   78,131.67x = 4,563,195,474.11
5. Step 5: Solve for x
   x = 4,563,195,474.11/78,131.67
6. Step 6: Final answer
   x = 58,403.92