Finding the Fourth Proportional to 20,601.32, 28,430.38 and 12,638.82

Step by Step Solution

1. Step 1: Write the proportion equation
   20,601.32 : 28,430.38 = 12,638.82 : x
2. Step 2: Convert to fraction form
   20,601.32/28,430.38 = 12,638.82/x
3. Step 3: Cross multiply
   20,601.32x = 28,430.38 × 12,638.82
4. Step 4: Simplify right side
   20,601.32x = 359,326,471.15
5. Step 5: Solve for x
   x = 359,326,471.15/20,601.32
6. Step 6: Final answer
   x = 17,441.91