Finding the Fourth Proportional to 8,677.50, 13,005.82 and 3,991.06

Step by Step Solution

1. Step 1: Write the proportion equation
   8,677.50 : 13,005.82 = 3,991.06 : x
2. Step 2: Convert to fraction form
   8,677.50/13,005.82 = 3,991.06/x
3. Step 3: Cross multiply
   8,677.50x = 13,005.82 × 3,991.06
4. Step 4: Simplify right side
   8,677.50x = 51,906,967.28
5. Step 5: Solve for x
   x = 51,906,967.28/8,677.50
6. Step 6: Final answer
   x = 5,981.78