Finding the Fourth Proportional to 12,607.91, 17,403.67 and 9,912.09

Step by Step Solution

1. Step 1: Write the proportion equation
   12,607.91 : 17,403.67 = 9,912.09 : x
2. Step 2: Convert to fraction form
   12,607.91/17,403.67 = 9,912.09/x
3. Step 3: Cross multiply
   12,607.91x = 17,403.67 × 9,912.09
4. Step 4: Simplify right side
   12,607.91x = 172,506,743.37
5. Step 5: Solve for x
   x = 172,506,743.37/12,607.91
6. Step 6: Final answer
   x = 13,682.42