Finding the Fourth Proportional to 31,080.22, 42,877.05 and 21,004.99

Step by Step Solution

1. Step 1: Write the proportion equation
   31,080.22 : 42,877.05 = 21,004.99 : x
2. Step 2: Convert to fraction form
   31,080.22/42,877.05 = 21,004.99/x
3. Step 3: Cross multiply
   31,080.22x = 42,877.05 × 21,004.99
4. Step 4: Simplify right side
   31,080.22x = 900,632,006.48
5. Step 5: Solve for x
   x = 900,632,006.48/31,080.22
6. Step 6: Final answer
   x = 28,977.66