Finding the Fourth Proportional to 31,098.84, 42,882.52 and 21,009.76

Step by Step Solution

1. Step 1: Write the proportion equation
   31,098.84 : 42,882.52 = 21,009.76 : x
2. Step 2: Convert to fraction form
   31,098.84/42,882.52 = 21,009.76/x
3. Step 3: Cross multiply
   31,098.84x = 42,882.52 × 21,009.76
4. Step 4: Simplify right side
   31,098.84x = 900,951,453.40
5. Step 5: Solve for x
   x = 900,951,453.40/31,098.84
6. Step 6: Final answer
   x = 28,970.58