Finding the Fourth Proportional to 12,900.74, 17,806.82 and 8,425.16

Step by Step Solution

1. Step 1: Write the proportion equation
   12,900.74 : 17,806.82 = 8,425.16 : x
2. Step 2: Convert to fraction form
   12,900.74/17,806.82 = 8,425.16/x
3. Step 3: Cross multiply
   12,900.74x = 17,806.82 × 8,425.16
4. Step 4: Simplify right side
   12,900.74x = 150,025,307.59
5. Step 5: Solve for x
   x = 150,025,307.59/12,900.74
6. Step 6: Final answer
   x = 11,629.20