Finding the Fourth Proportional to 78,391.86, 117,507.32 and 30,987.69

Step by Step Solution

1. Step 1: Write the proportion equation
   78,391.86 : 117,507.32 = 30,987.69 : x
2. Step 2: Convert to fraction form
   78,391.86/117,507.32 = 30,987.69/x
3. Step 3: Cross multiply
   78,391.86x = 117,507.32 × 30,987.69
4. Step 4: Simplify right side
   78,391.86x = 3,641,280,404.89
5. Step 5: Solve for x
   x = 3,641,280,404.89/78,391.86
6. Step 6: Final answer
   x = 46,449.73