Finding the Fourth Proportional to 31,112.28, 42,954.30 and 19,788.12

Step by Step Solution

1. Step 1: Write the proportion equation
   31,112.28 : 42,954.30 = 19,788.12 : x
2. Step 2: Convert to fraction form
   31,112.28/42,954.30 = 19,788.12/x
3. Step 3: Cross multiply
   31,112.28x = 42,954.30 × 19,788.12
4. Step 4: Simplify right side
   31,112.28x = 849,984,842.92
5. Step 5: Solve for x
   x = 849,984,842.92/31,112.28
6. Step 6: Final answer
   x = 27,319.91