Finding the Fourth Proportional to 13,618.73, 20,417.71 and 7,040.72

Step by Step Solution

1. Step 1: Write the proportion equation
   13,618.73 : 20,417.71 = 7,040.72 : x
2. Step 2: Convert to fraction form
   13,618.73/20,417.71 = 7,040.72/x
3. Step 3: Cross multiply
   13,618.73x = 20,417.71 × 7,040.72
4. Step 4: Simplify right side
   13,618.73x = 143,755,379.15
5. Step 5: Solve for x
   x = 143,755,379.15/13,618.73
6. Step 6: Final answer
   x = 10,555.71