Finding the Fourth Proportional to 13,078.61, 18,051.10 and 7,772.40

Step by Step Solution

1. Step 1: Write the proportion equation
   13,078.61 : 18,051.10 = 7,772.40 : x
2. Step 2: Convert to fraction form
   13,078.61/18,051.10 = 7,772.40/x
3. Step 3: Cross multiply
   13,078.61x = 18,051.10 × 7,772.40
4. Step 4: Simplify right side
   13,078.61x = 140,300,369.64
5. Step 5: Solve for x
   x = 140,300,369.64/13,078.61
6. Step 6: Final answer
   x = 10,727.47