Finding the Fourth Proportional to 13,505.95, 18,639.15 and 7,538.79

Step by Step Solution

1. Step 1: Write the proportion equation
   13,505.95 : 18,639.15 = 7,538.79 : x
2. Step 2: Convert to fraction form
   13,505.95/18,639.15 = 7,538.79/x
3. Step 3: Cross multiply
   13,505.95x = 18,639.15 × 7,538.79
4. Step 4: Simplify right side
   13,505.95x = 140,516,591.03
5. Step 5: Solve for x
   x = 140,516,591.03/13,505.95
6. Step 6: Final answer
   x = 10,404.05