Finding the Fourth Proportional to 13,508.50, 18,643.89 and 7,919.50

Step by Step Solution

1. Step 1: Write the proportion equation
   13,508.50 : 18,643.89 = 7,919.50 : x
2. Step 2: Convert to fraction form
   13,508.50/18,643.89 = 7,919.50/x
3. Step 3: Cross multiply
   13,508.50x = 18,643.89 × 7,919.50
4. Step 4: Simplify right side
   13,508.50x = 147,650,286.86
5. Step 5: Solve for x
   x = 147,650,286.86/13,508.50
6. Step 6: Final answer
   x = 10,930.18