Finding the Fourth Proportional to 42,405.78, 63,821.40 and 31,930.08

Step by Step Solution

1. Step 1: Write the proportion equation
   42,405.78 : 63,821.40 = 31,930.08 : x
2. Step 2: Convert to fraction form
   42,405.78/63,821.40 = 31,930.08/x
3. Step 3: Cross multiply
   42,405.78x = 63,821.40 × 31,930.08
4. Step 4: Simplify right side
   42,405.78x = 2,037,822,407.71
5. Step 5: Solve for x
   x = 2,037,822,407.71/42,405.78
6. Step 6: Final answer
   x = 48,055.30