Finding the Fourth Proportional to 30,989.56, 42,765.88 and 18,411.88

Step by Step Solution

1. Step 1: Write the proportion equation
   30,989.56 : 42,765.88 = 18,411.88 : x
2. Step 2: Convert to fraction form
   30,989.56/42,765.88 = 18,411.88/x
3. Step 3: Cross multiply
   30,989.56x = 42,765.88 × 18,411.88
4. Step 4: Simplify right side
   30,989.56x = 787,400,036.83
5. Step 5: Solve for x
   x = 787,400,036.83/30,989.56
6. Step 6: Final answer
   x = 25,408.56