Finding the Fourth Proportional to 12,892.71, 17,790.35 and 7,855.10

Step by Step Solution

1. Step 1: Write the proportion equation
   12,892.71 : 17,790.35 = 7,855.10 : x
2. Step 2: Convert to fraction form
   12,892.71/17,790.35 = 7,855.10/x
3. Step 3: Cross multiply
   12,892.71x = 17,790.35 × 7,855.10
4. Step 4: Simplify right side
   12,892.71x = 139,744,978.29
5. Step 5: Solve for x
   x = 139,744,978.29/12,892.71
6. Step 6: Final answer
   x = 10,839.07