Finding the Fourth Proportional to 99,981.09, 137,986.86 and 56,976.12

Step by Step Solution

1. Step 1: Write the proportion equation
   99,981.09 : 137,986.86 = 56,976.12 : x
2. Step 2: Convert to fraction form
   99,981.09/137,986.86 = 56,976.12/x
3. Step 3: Cross multiply
   99,981.09x = 137,986.86 × 56,976.12
4. Step 4: Simplify right side
   99,981.09x = 7,861,955,893.78
5. Step 5: Solve for x
   x = 7,861,955,893.78/99,981.09
6. Step 6: Final answer
   x = 78,634.43