Finding the Fourth Proportional to 17,129.30, 25,643.55 and 12,766.10

Step by Step Solution

1. Step 1: Write the proportion equation
   17,129.30 : 25,643.55 = 12,766.10 : x
2. Step 2: Convert to fraction form
   17,129.30/25,643.55 = 12,766.10/x
3. Step 3: Cross multiply
   17,129.30x = 25,643.55 × 12,766.10
4. Step 4: Simplify right side
   17,129.30x = 327,368,123.66
5. Step 5: Solve for x
   x = 327,368,123.66/17,129.30
6. Step 6: Final answer
   x = 19,111.59