Finding the Fourth Proportional to 31,086.72, 42,871.68 and 19,906.56

Step by Step Solution

1. Step 1: Write the proportion equation
   31,086.72 : 42,871.68 = 19,906.56 : x
2. Step 2: Convert to fraction form
   31,086.72/42,871.68 = 19,906.56/x
3. Step 3: Cross multiply
   31,086.72x = 42,871.68 × 19,906.56
4. Step 4: Simplify right side
   31,086.72x = 853,427,670.22
5. Step 5: Solve for x
   x = 853,427,670.22/31,086.72
6. Step 6: Final answer
   x = 27,453.13