Finding the Fourth Proportional to 13,066.61, 18,027.20 and 7,761.30

Step by Step Solution

1. Step 1: Write the proportion equation
   13,066.61 : 18,027.20 = 7,761.30 : x
2. Step 2: Convert to fraction form
   13,066.61/18,027.20 = 7,761.30/x
3. Step 3: Cross multiply
   13,066.61x = 18,027.20 × 7,761.30
4. Step 4: Simplify right side
   13,066.61x = 139,914,468.55
5. Step 5: Solve for x
   x = 139,914,468.55/13,066.61
6. Step 6: Final answer
   x = 10,707.79