Finding the Fourth Proportional to 11,165.48, 15,399.57 and 9,890.72

Step by Step Solution

1. Step 1: Write the proportion equation
   11,165.48 : 15,399.57 = 9,890.72 : x
2. Step 2: Convert to fraction form
   11,165.48/15,399.57 = 9,890.72/x
3. Step 3: Cross multiply
   11,165.48x = 15,399.57 × 9,890.72
4. Step 4: Simplify right side
   11,165.48x = 152,312,834.99
5. Step 5: Solve for x
   x = 152,312,834.99/11,165.48
6. Step 6: Final answer
   x = 13,641.41