Finding the Fourth Proportional to 12,990.72, 17,928.72 and 12,582.48

Step by Step Solution

1. Step 1: Write the proportion equation
   12,990.72 : 17,928.72 = 12,582.48 : x
2. Step 2: Convert to fraction form
   12,990.72/17,928.72 = 12,582.48/x
3. Step 3: Cross multiply
   12,990.72x = 17,928.72 × 12,582.48
4. Step 4: Simplify right side
   12,990.72x = 225,587,760.83
5. Step 5: Solve for x
   x = 225,587,760.83/12,990.72
6. Step 6: Final answer
   x = 17,365.30