Finding the Fourth Proportional to 644,061.07, 964,596.70 and 621,641.59

Step by Step Solution

1. Step 1: Write the proportion equation
   644,061.07 : 964,596.70 = 621,641.59 : x
2. Step 2: Convert to fraction form
   644,061.07/964,596.70 = 621,641.59/x
3. Step 3: Cross multiply
   644,061.07x = 964,596.70 × 621,641.59
4. Step 4: Simplify right side
   644,061.07x = 599,633,424,662.31
5. Step 5: Solve for x
   x = 599,633,424,662.31/644,061.07
6. Step 6: Final answer
   x = 931,019.51