Finding the Fourth Proportional to 426,315.18, 639,096.53 and 173,806.89

Step by Step Solution

1. Step 1: Write the proportion equation
   426,315.18 : 639,096.53 = 173,806.89 : x
2. Step 2: Convert to fraction form
   426,315.18/639,096.53 = 173,806.89/x
3. Step 3: Cross multiply
   426,315.18x = 639,096.53 × 173,806.89
4. Step 4: Simplify right side
   426,315.18x = 111,079,379,798.57
5. Step 5: Solve for x
   x = 111,079,379,798.57/426,315.18
6. Step 6: Final answer
   x = 260,556.95