Finding the Fourth Proportional to 42,481.63, 63,718.32 and 12,899.72

Step by Step Solution

1. Step 1: Write the proportion equation
   42,481.63 : 63,718.32 = 12,899.72 : x
2. Step 2: Convert to fraction form
   42,481.63/63,718.32 = 12,899.72/x
3. Step 3: Cross multiply
   42,481.63x = 63,718.32 × 12,899.72
4. Step 4: Simplify right side
   42,481.63x = 821,948,389.45
5. Step 5: Solve for x
   x = 821,948,389.45/42,481.63
6. Step 6: Final answer
   x = 19,348.33