Finding the Fourth Proportional to 12,930.78, 17,830.35 and 8,731.74

Step by Step Solution

1. Step 1: Write the proportion equation
   12,930.78 : 17,830.35 = 8,731.74 : x
2. Step 2: Convert to fraction form
   12,930.78/17,830.35 = 8,731.74/x
3. Step 3: Cross multiply
   12,930.78x = 17,830.35 × 8,731.74
4. Step 4: Simplify right side
   12,930.78x = 155,689,980.31
5. Step 5: Solve for x
   x = 155,689,980.31/12,930.78
6. Step 6: Final answer
   x = 12,040.26