Finding the Fourth Proportional to 639,016.46, 953,291.55 and 621,642.09

Step by Step Solution

1. Step 1: Write the proportion equation
   639,016.46 : 953,291.55 = 621,642.09 : x
2. Step 2: Convert to fraction form
   639,016.46/953,291.55 = 621,642.09/x
3. Step 3: Cross multiply
   639,016.46x = 953,291.55 × 621,642.09
4. Step 4: Simplify right side
   639,016.46x = 592,606,151,521.34
5. Step 5: Solve for x
   x = 592,606,151,521.34/639,016.46
6. Step 6: Final answer
   x = 927,372.28