Finding the Fourth Proportional to 12,889.20, 17,788.58 and 7,225.48

Step by Step Solution

1. Step 1: Write the proportion equation
   12,889.20 : 17,788.58 = 7,225.48 : x
2. Step 2: Convert to fraction form
   12,889.20/17,788.58 = 7,225.48/x
3. Step 3: Cross multiply
   12,889.20x = 17,788.58 × 7,225.48
4. Step 4: Simplify right side
   12,889.20x = 128,530,992.89
5. Step 5: Solve for x
   x = 128,530,992.89/12,889.20
6. Step 6: Final answer
   x = 9,971.99