Finding the Fourth Proportional to 83,780.69, 115,498.37 and 66,634.61

Step by Step Solution

1. Step 1: Write the proportion equation
   83,780.69 : 115,498.37 = 66,634.61 : x
2. Step 2: Convert to fraction form
   83,780.69/115,498.37 = 66,634.61/x
3. Step 3: Cross multiply
   83,780.69x = 115,498.37 × 66,634.61
4. Step 4: Simplify right side
   83,780.69x = 7,696,188,263.09
5. Step 5: Solve for x
   x = 7,696,188,263.09/83,780.69
6. Step 6: Final answer
   x = 91,861.13