Finding the Fourth Proportional to 21,854.94, 30,173.61 and 15,138.15

Step by Step Solution

1. Step 1: Write the proportion equation
   21,854.94 : 30,173.61 = 15,138.15 : x
2. Step 2: Convert to fraction form
   21,854.94/30,173.61 = 15,138.15/x
3. Step 3: Cross multiply
   21,854.94x = 30,173.61 × 15,138.15
4. Step 4: Simplify right side
   21,854.94x = 456,772,634.22
5. Step 5: Solve for x
   x = 456,772,634.22/21,854.94
6. Step 6: Final answer
   x = 20,900.20