Finding the Fourth Proportional to 388,719.06, 536,411.61 and 218,942.25

Step by Step Solution

1. Step 1: Write the proportion equation
   388,719.06 : 536,411.61 = 218,942.25 : x
2. Step 2: Convert to fraction form
   388,719.06/536,411.61 = 218,942.25/x
3. Step 3: Cross multiply
   388,719.06x = 536,411.61 × 218,942.25
4. Step 4: Simplify right side
   388,719.06x = 117,443,164,819.52
5. Step 5: Solve for x
   x = 117,443,164,819.52/388,719.06
6. Step 6: Final answer
   x = 302,128.65