Finding the Fourth Proportional to 40,590.72, 60,897.60 and 12,890.88

Step by Step Solution

1. Step 1: Write the proportion equation
   40,590.72 : 60,897.60 = 12,890.88 : x
2. Step 2: Convert to fraction form
   40,590.72/60,897.60 = 12,890.88/x
3. Step 3: Cross multiply
   40,590.72x = 60,897.60 × 12,890.88
4. Step 4: Simplify right side
   40,590.72x = 785,023,653.89
5. Step 5: Solve for x
   x = 785,023,653.89/40,590.72
6. Step 6: Final answer
   x = 19,339.98