Finding the Fourth Proportional to 91,913.81, 137,987.37 and 78,150.29

Step by Step Solution

1. Step 1: Write the proportion equation
   91,913.81 : 137,987.37 = 78,150.29 : x
2. Step 2: Convert to fraction form
   91,913.81/137,987.37 = 78,150.29/x
3. Step 3: Cross multiply
   91,913.81x = 137,987.37 × 78,150.29
4. Step 4: Simplify right side
   91,913.81x = 10,783,752,291.90
5. Step 5: Solve for x
   x = 10,783,752,291.90/91,913.81
6. Step 6: Final answer
   x = 117,324.62