Finding the Fourth Proportional to 31,006.58, 42,789.21 and 18,431.42

Step by Step Solution

1. Step 1: Write the proportion equation
   31,006.58 : 42,789.21 = 18,431.42 : x
2. Step 2: Convert to fraction form
   31,006.58/42,789.21 = 18,431.42/x
3. Step 3: Cross multiply
   31,006.58x = 42,789.21 × 18,431.42
4. Step 4: Simplify right side
   31,006.58x = 788,665,900.98
5. Step 5: Solve for x
   x = 788,665,900.98/31,006.58
6. Step 6: Final answer
   x = 25,435.44