Finding the Fourth Proportional to 42,540.10, 63,819.66 and 12,960.25

Step by Step Solution

1. Step 1: Write the proportion equation
   42,540.10 : 63,819.66 = 12,960.25 : x
2. Step 2: Convert to fraction form
   42,540.10/63,819.66 = 12,960.25/x
3. Step 3: Cross multiply
   42,540.10x = 63,819.66 × 12,960.25
4. Step 4: Simplify right side
   42,540.10x = 827,118,748.52
5. Step 5: Solve for x
   x = 827,118,748.52/42,540.10
6. Step 6: Final answer
   x = 19,443.27