Finding the Fourth Proportional to 31,078.80, 42,888.24 and 16,931.88

Step by Step Solution

1. Step 1: Write the proportion equation
   31,078.80 : 42,888.24 = 16,931.88 : x
2. Step 2: Convert to fraction form
   31,078.80/42,888.24 = 16,931.88/x
3. Step 3: Cross multiply
   31,078.80x = 42,888.24 × 16,931.88
4. Step 4: Simplify right side
   31,078.80x = 726,178,533.09
5. Step 5: Solve for x
   x = 726,178,533.09/31,078.80
6. Step 6: Final answer
   x = 23,365.72