Finding the Fourth Proportional to 31,111.28, 42,937.73 and 19,781.90

Step by Step Solution

1. Step 1: Write the proportion equation
   31,111.28 : 42,937.73 = 19,781.90 : x
2. Step 2: Convert to fraction form
   31,111.28/42,937.73 = 19,781.90/x
3. Step 3: Cross multiply
   31,111.28x = 42,937.73 × 19,781.90
4. Step 4: Simplify right side
   31,111.28x = 849,389,567.49
5. Step 5: Solve for x
   x = 849,389,567.49/31,111.28
6. Step 6: Final answer
   x = 27,301.66