Finding the Fourth Proportional to 13,116.77, 18,100.61 and 7,148.31

Step by Step Solution

1. Step 1: Write the proportion equation
   13,116.77 : 18,100.61 = 7,148.31 : x
2. Step 2: Convert to fraction form
   13,116.77/18,100.61 = 7,148.31/x
3. Step 3: Cross multiply
   13,116.77x = 18,100.61 × 7,148.31
4. Step 4: Simplify right side
   13,116.77x = 129,388,771.47
5. Step 5: Solve for x
   x = 129,388,771.47/13,116.77
6. Step 6: Final answer
   x = 9,864.38