Finding the Fourth Proportional to 12,931.90, 17,845.55 and 7,904.54

Step by Step Solution

1. Step 1: Write the proportion equation
   12,931.90 : 17,845.55 = 7,904.54 : x
2. Step 2: Convert to fraction form
   12,931.90/17,845.55 = 7,904.54/x
3. Step 3: Cross multiply
   12,931.90x = 17,845.55 × 7,904.54
4. Step 4: Simplify right side
   12,931.90x = 141,060,863.80
5. Step 5: Solve for x
   x = 141,060,863.80/12,931.90
6. Step 6: Final answer
   x = 10,907.98