Finding the Fourth Proportional to 13,238.28, 19,865.79 and 7,398.72

Step by Step Solution

1. Step 1: Write the proportion equation
   13,238.28 : 19,865.79 = 7,398.72 : x
2. Step 2: Convert to fraction form
   13,238.28/19,865.79 = 7,398.72/x
3. Step 3: Cross multiply
   13,238.28x = 19,865.79 × 7,398.72
4. Step 4: Simplify right side
   13,238.28x = 146,981,417.79
5. Step 5: Solve for x
   x = 146,981,417.79/13,238.28
6. Step 6: Final answer
   x = 11,102.76