Finding the Fourth Proportional to 31,140.32, 42,959.92 and 21,065.08

Step by Step Solution

1. Step 1: Write the proportion equation
   31,140.32 : 42,959.92 = 21,065.08 : x
2. Step 2: Convert to fraction form
   31,140.32/42,959.92 = 21,065.08/x
3. Step 3: Cross multiply
   31,140.32x = 42,959.92 × 21,065.08
4. Step 4: Simplify right side
   31,140.32x = 904,954,151.59
5. Step 5: Solve for x
   x = 904,954,151.59/31,140.32
6. Step 6: Final answer
   x = 29,060.53