Finding the Fourth Proportional to 31,139.36, 42,959.22 and 21,713.39

Step by Step Solution

1. Step 1: Write the proportion equation
   31,139.36 : 42,959.22 = 21,713.39 : x
2. Step 2: Convert to fraction form
   31,139.36/42,959.22 = 21,713.39/x
3. Step 3: Cross multiply
   31,139.36x = 42,959.22 × 21,713.39
4. Step 4: Simplify right side
   31,139.36x = 932,790,297.96
5. Step 5: Solve for x
   x = 932,790,297.96/31,139.36
6. Step 6: Final answer
   x = 29,955.35