Finding the Fourth Proportional to 8,978.18, 12,389.81 and 4,999.19

Step by Step Solution

1. Step 1: Write the proportion equation
   8,978.18 : 12,389.81 = 4,999.19 : x
2. Step 2: Convert to fraction form
   8,978.18/12,389.81 = 4,999.19/x
3. Step 3: Cross multiply
   8,978.18x = 12,389.81 × 4,999.19
4. Step 4: Simplify right side
   8,978.18x = 61,938,927.31
5. Step 5: Solve for x
   x = 61,938,927.31/8,978.18
6. Step 6: Final answer
   x = 6,898.83