Finding the Fourth Proportional to 9,721.89, 13,422.31 and 7,713.50

Step by Step Solution

1. Step 1: Write the proportion equation
   9,721.89 : 13,422.31 = 7,713.50 : x
2. Step 2: Convert to fraction form
   9,721.89/13,422.31 = 7,713.50/x
3. Step 3: Cross multiply
   9,721.89x = 13,422.31 × 7,713.50
4. Step 4: Simplify right side
   9,721.89x = 103,532,901.79
5. Step 5: Solve for x
   x = 103,532,901.79/9,721.89
6. Step 6: Final answer
   x = 10,649.46