Finding the Fourth Proportional to 663,198.72, 915,215.40 and 361,392.72

Step by Step Solution

1. Step 1: Write the proportion equation
   663,198.72 : 915,215.40 = 361,392.72 : x
2. Step 2: Convert to fraction form
   663,198.72/915,215.40 = 361,392.72/x
3. Step 3: Cross multiply
   663,198.72x = 915,215.40 × 361,392.72
4. Step 4: Simplify right side
   663,198.72x = 330,752,182,791.89
5. Step 5: Solve for x
   x = 330,752,182,791.89/663,198.72
6. Step 6: Final answer
   x = 498,722.59