Finding the Fourth Proportional to 31,415.89, 43,356.42 and 17,991.37

Step by Step Solution

1. Step 1: Write the proportion equation
   31,415.89 : 43,356.42 = 17,991.37 : x
2. Step 2: Convert to fraction form
   31,415.89/43,356.42 = 17,991.37/x
3. Step 3: Cross multiply
   31,415.89x = 43,356.42 × 17,991.37
4. Step 4: Simplify right side
   31,415.89x = 780,041,394.10
5. Step 5: Solve for x
   x = 780,041,394.10/31,415.89
6. Step 6: Final answer
   x = 24,829.52