Finding the Fourth Proportional to 13,689.82, 18,891.91 and 7,402.19

Step by Step Solution

1. Step 1: Write the proportion equation
   13,689.82 : 18,891.91 = 7,402.19 : x
2. Step 2: Convert to fraction form
   13,689.82/18,891.91 = 7,402.19/x
3. Step 3: Cross multiply
   13,689.82x = 18,891.91 × 7,402.19
4. Step 4: Simplify right side
   13,689.82x = 139,841,470.27
5. Step 5: Solve for x
   x = 139,841,470.27/13,689.82
6. Step 6: Final answer
   x = 10,215.00