Finding the Fourth Proportional to 10,215.04, 15,392.05 and 8,406.72

Step by Step Solution

1. Step 1: Write the proportion equation
   10,215.04 : 15,392.05 = 8,406.72 : x
2. Step 2: Convert to fraction form
   10,215.04/15,392.05 = 8,406.72/x
3. Step 3: Cross multiply
   10,215.04x = 15,392.05 × 8,406.72
4. Step 4: Simplify right side
   10,215.04x = 129,396,654.58
5. Step 5: Solve for x
   x = 129,396,654.58/10,215.04
6. Step 6: Final answer
   x = 12,667.27