Finding the Fourth Proportional to 30,835.98, 42,490.83 and 21,278.79

Step by Step Solution

1. Step 1: Write the proportion equation
   30,835.98 : 42,490.83 = 21,278.79 : x
2. Step 2: Convert to fraction form
   30,835.98/42,490.83 = 21,278.79/x
3. Step 3: Cross multiply
   30,835.98x = 42,490.83 × 21,278.79
4. Step 4: Simplify right side
   30,835.98x = 904,153,448.50
5. Step 5: Solve for x
   x = 904,153,448.50/30,835.98
6. Step 6: Final answer
   x = 29,321.38