Finding the Fourth Proportional to 31,079.09, 42,892.25 and 18,978.91

Step by Step Solution

1. Step 1: Write the proportion equation
   31,079.09 : 42,892.25 = 18,978.91 : x
2. Step 2: Convert to fraction form
   31,079.09/42,892.25 = 18,978.91/x
3. Step 3: Cross multiply
   31,079.09x = 42,892.25 × 18,978.91
4. Step 4: Simplify right side
   31,079.09x = 814,047,950.32
5. Step 5: Solve for x
   x = 814,047,950.32/31,079.09
6. Step 6: Final answer
   x = 26,192.78