Finding the Fourth Proportional to 31,087.20, 42,916.14 and 21,068.52

Step by Step Solution

1. Step 1: Write the proportion equation
   31,087.20 : 42,916.14 = 21,068.52 : x
2. Step 2: Convert to fraction form
   31,087.20/42,916.14 = 21,068.52/x
3. Step 3: Cross multiply
   31,087.20x = 42,916.14 × 21,068.52
4. Step 4: Simplify right side
   31,087.20x = 904,179,553.91
5. Step 5: Solve for x
   x = 904,179,553.91/31,087.20
6. Step 6: Final answer
   x = 29,085.27