Finding the Fourth Proportional to 9,855.31, 13,612.89 and 7,572.80

Step by Step Solution

1. Step 1: Write the proportion equation
   9,855.31 : 13,612.89 = 7,572.80 : x
2. Step 2: Convert to fraction form
   9,855.31/13,612.89 = 7,572.80/x
3. Step 3: Cross multiply
   9,855.31x = 13,612.89 × 7,572.80
4. Step 4: Simplify right side
   9,855.31x = 103,087,693.39
5. Step 5: Solve for x
   x = 103,087,693.39/9,855.31
6. Step 6: Final answer
   x = 10,460.12