Finding the Fourth Proportional to 13,559.48, 18,711.90 and 7,591.15

Step by Step Solution

1. Step 1: Write the proportion equation
   13,559.48 : 18,711.90 = 7,591.15 : x
2. Step 2: Convert to fraction form
   13,559.48/18,711.90 = 7,591.15/x
3. Step 3: Cross multiply
   13,559.48x = 18,711.90 × 7,591.15
4. Step 4: Simplify right side
   13,559.48x = 142,044,839.69
5. Step 5: Solve for x
   x = 142,044,839.69/13,559.48
6. Step 6: Final answer
   x = 10,475.68