Finding the Fourth Proportional to 139,390.72, 209,084.80 and 56,283.52

Step by Step Solution

1. Step 1: Write the proportion equation
   139,390.72 : 209,084.80 = 56,283.52 : x
2. Step 2: Convert to fraction form
   139,390.72/209,084.80 = 56,283.52/x
3. Step 3: Cross multiply
   139,390.72x = 209,084.80 × 56,283.52
4. Step 4: Simplify right side
   139,390.72x = 11,768,028,522.50
5. Step 5: Solve for x
   x = 11,768,028,522.50/139,390.72
6. Step 6: Final answer
   x = 84,424.76