Finding the Fourth Proportional to 42,167.70, 63,309.15 and 21,405.78

Step by Step Solution

1. Step 1: Write the proportion equation
   42,167.70 : 63,309.15 = 21,405.78 : x
2. Step 2: Convert to fraction form
   42,167.70/63,309.15 = 21,405.78/x
3. Step 3: Cross multiply
   42,167.70x = 63,309.15 × 21,405.78
4. Step 4: Simplify right side
   42,167.70x = 1,355,181,736.89
5. Step 5: Solve for x
   x = 1,355,181,736.89/42,167.70
6. Step 6: Final answer
   x = 32,137.91