Finding the Fourth Proportional to 21,014.72, 31,518.72 and 13,671.36

Step by Step Solution

1. Step 1: Write the proportion equation
   21,014.72 : 31,518.72 = 13,671.36 : x
2. Step 2: Convert to fraction form
   21,014.72/31,518.72 = 13,671.36/x
3. Step 3: Cross multiply
   21,014.72x = 31,518.72 × 13,671.36
4. Step 4: Simplify right side
   21,014.72x = 430,903,767.86
5. Step 5: Solve for x
   x = 430,903,767.86/21,014.72
6. Step 6: Final answer
   x = 20,504.85