Finding the Fourth Proportional to 420,499.89, 580,221.43 and 248,394.06

Step by Step Solution

1. Step 1: Write the proportion equation
   420,499.89 : 580,221.43 = 248,394.06 : x
2. Step 2: Convert to fraction form
   420,499.89/580,221.43 = 248,394.06/x
3. Step 3: Cross multiply
   420,499.89x = 580,221.43 × 248,394.06
4. Step 4: Simplify right side
   420,499.89x = 144,123,556,075.72
5. Step 5: Solve for x
   x = 144,123,556,075.72/420,499.89
6. Step 6: Final answer
   x = 342,743.39