Finding the Fourth Proportional to 42,012.90, 63,031.59 and 12,431.52

Step by Step Solution

1. Step 1: Write the proportion equation
   42,012.90 : 63,031.59 = 12,431.52 : x
2. Step 2: Convert to fraction form
   42,012.90/63,031.59 = 12,431.52/x
3. Step 3: Cross multiply
   42,012.90x = 63,031.59 × 12,431.52
4. Step 4: Simplify right side
   42,012.90x = 783,578,471.72
5. Step 5: Solve for x
   x = 783,578,471.72/42,012.90
6. Step 6: Final answer
   x = 18,650.90