Finding the Fourth Proportional to 30,557.25, 42,155.64 and 21,612.42

Step by Step Solution

1. Step 1: Write the proportion equation
   30,557.25 : 42,155.64 = 21,612.42 : x
2. Step 2: Convert to fraction form
   30,557.25/42,155.64 = 21,612.42/x
3. Step 3: Cross multiply
   30,557.25x = 42,155.64 × 21,612.42
4. Step 4: Simplify right side
   30,557.25x = 911,085,397.05
5. Step 5: Solve for x
   x = 911,085,397.05/30,557.25
6. Step 6: Final answer
   x = 29,815.69