Finding the Fourth Proportional to 21,777.31, 30,050.89 and 12,215.87

Step by Step Solution

1. Step 1: Write the proportion equation
   21,777.31 : 30,050.89 = 12,215.87 : x
2. Step 2: Convert to fraction form
   21,777.31/30,050.89 = 12,215.87/x
3. Step 3: Cross multiply
   21,777.31x = 30,050.89 × 12,215.87
4. Step 4: Simplify right side
   21,777.31x = 367,097,697.52
5. Step 5: Solve for x
   x = 367,097,697.52/21,777.31
6. Step 6: Final answer
   x = 16,856.89