Finding the Fourth Proportional to 258,375.79, 387,538.59 and 78,462.78

Step by Step Solution

1. Step 1: Write the proportion equation
   258,375.79 : 387,538.59 = 78,462.78 : x
2. Step 2: Convert to fraction form
   258,375.79/387,538.59 = 78,462.78/x
3. Step 3: Cross multiply
   258,375.79x = 387,538.59 × 78,462.78
4. Step 4: Simplify right side
   258,375.79x = 30,407,353,969.65
5. Step 5: Solve for x
   x = 30,407,353,969.65/258,375.79
6. Step 6: Final answer
   x = 117,686.54