Finding the Fourth Proportional to 31,128.74, 42,957.48 and 16,981.58

Step by Step Solution

1. Step 1: Write the proportion equation
   31,128.74 : 42,957.48 = 16,981.58 : x
2. Step 2: Convert to fraction form
   31,128.74/42,957.48 = 16,981.58/x
3. Step 3: Cross multiply
   31,128.74x = 42,957.48 × 16,981.58
4. Step 4: Simplify right side
   31,128.74x = 729,485,883.22
5. Step 5: Solve for x
   x = 729,485,883.22/31,128.74
6. Step 6: Final answer
   x = 23,434.48