Finding the Fourth Proportional to 21,870.99, 30,149.70 and 15,477.72

Step by Step Solution

1. Step 1: Write the proportion equation
   21,870.99 : 30,149.70 = 15,477.72 : x
2. Step 2: Convert to fraction form
   21,870.99/30,149.70 = 15,477.72/x
3. Step 3: Cross multiply
   21,870.99x = 30,149.70 × 15,477.72
4. Step 4: Simplify right side
   21,870.99x = 466,648,614.68
5. Step 5: Solve for x
   x = 466,648,614.68/21,870.99
6. Step 6: Final answer
   x = 21,336.42