Finding the Fourth Proportional to 13,288.91, 19,931.67 and 3,928.73

Step by Step Solution

1. Step 1: Write the proportion equation
   13,288.91 : 19,931.67 = 3,928.73 : x
2. Step 2: Convert to fraction form
   13,288.91/19,931.67 = 3,928.73/x
3. Step 3: Cross multiply
   13,288.91x = 19,931.67 × 3,928.73
4. Step 4: Simplify right side
   13,288.91x = 78,306,149.88
5. Step 5: Solve for x
   x = 78,306,149.88/13,288.91
6. Step 6: Final answer
   x = 5,892.59