Finding the Fourth Proportional to 378,870.96, 522,839.34 and 209,105.10

Step by Step Solution

1. Step 1: Write the proportion equation
   378,870.96 : 522,839.34 = 209,105.10 : x
2. Step 2: Convert to fraction form
   378,870.96/522,839.34 = 209,105.10/x
3. Step 3: Cross multiply
   378,870.96x = 522,839.34 × 209,105.10
4. Step 4: Simplify right side
   378,870.96x = 109,328,372,474.63
5. Step 5: Solve for x
   x = 109,328,372,474.63/378,870.96
6. Step 6: Final answer
   x = 288,563.61