Finding the Fourth Proportional to 12,931.79, 17,845.36 and 7,904.42

Step by Step Solution

1. Step 1: Write the proportion equation
   12,931.79 : 17,845.36 = 7,904.42 : x
2. Step 2: Convert to fraction form
   12,931.79/17,845.36 = 7,904.42/x
3. Step 3: Cross multiply
   12,931.79x = 17,845.36 × 7,904.42
4. Step 4: Simplify right side
   12,931.79x = 141,057,220.49
5. Step 5: Solve for x
   x = 141,057,220.49/12,931.79
6. Step 6: Final answer
   x = 10,907.79