Finding the Fourth Proportional to 86,816.88, 130,012.92 and 78,402.42

Step by Step Solution

1. Step 1: Write the proportion equation
   86,816.88 : 130,012.92 = 78,402.42 : x
2. Step 2: Convert to fraction form
   86,816.88/130,012.92 = 78,402.42/x
3. Step 3: Cross multiply
   86,816.88x = 130,012.92 × 78,402.42
4. Step 4: Simplify right side
   86,816.88x = 10,193,327,559.27
5. Step 5: Solve for x
   x = 10,193,327,559.27/86,816.88
6. Step 6: Final answer
   x = 117,411.82