Finding the Fourth Proportional to 12,069.90, 18,111.30 and 5,142.78

Step by Step Solution

1. Step 1: Write the proportion equation
   12,069.90 : 18,111.30 = 5,142.78 : x
2. Step 2: Convert to fraction form
   12,069.90/18,111.30 = 5,142.78/x
3. Step 3: Cross multiply
   12,069.90x = 18,111.30 × 5,142.78
4. Step 4: Simplify right side
   12,069.90x = 93,142,431.41
5. Step 5: Solve for x
   x = 93,142,431.41/12,069.90
6. Step 6: Final answer
   x = 7,716.92