Finding the Fourth Proportional to 13,731.30, 20,640.15 and 13,472.10

Step by Step Solution

1. Step 1: Write the proportion equation
   13,731.30 : 20,640.15 = 13,472.10 : x
2. Step 2: Convert to fraction form
   13,731.30/20,640.15 = 13,472.10/x
3. Step 3: Cross multiply
   13,731.30x = 20,640.15 × 13,472.10
4. Step 4: Simplify right side
   13,731.30x = 278,066,164.82
5. Step 5: Solve for x
   x = 278,066,164.82/13,731.30
6. Step 6: Final answer
   x = 20,250.53