Finding the Fourth Proportional to 9,708.72, 13,402.86 and 7,421.49

Step by Step Solution

1. Step 1: Write the proportion equation
   9,708.72 : 13,402.86 = 7,421.49 : x
2. Step 2: Convert to fraction form
   9,708.72/13,402.86 = 7,421.49/x
3. Step 3: Cross multiply
   9,708.72x = 13,402.86 × 7,421.49
4. Step 4: Simplify right side
   9,708.72x = 99,469,191.46
5. Step 5: Solve for x
   x = 99,469,191.46/9,708.72
6. Step 6: Final answer
   x = 10,245.35