Finding the Fourth Proportional to 30,925.92, 42,688.02 and 21,999.31

Step by Step Solution

1. Step 1: Write the proportion equation
   30,925.92 : 42,688.02 = 21,999.31 : x
2. Step 2: Convert to fraction form
   30,925.92/42,688.02 = 21,999.31/x
3. Step 3: Cross multiply
   30,925.92x = 42,688.02 × 21,999.31
4. Step 4: Simplify right side
   30,925.92x = 939,106,985.27
5. Step 5: Solve for x
   x = 939,106,985.27/30,925.92
6. Step 6: Final answer
   x = 30,366.34