Finding the Fourth Proportional to 15,123.49, 20,870.30 and 8,409.06

Step by Step Solution

1. Step 1: Write the proportion equation
   15,123.49 : 20,870.30 = 8,409.06 : x
2. Step 2: Convert to fraction form
   15,123.49/20,870.30 = 8,409.06/x
3. Step 3: Cross multiply
   15,123.49x = 20,870.30 × 8,409.06
4. Step 4: Simplify right side
   15,123.49x = 175,499,604.92
5. Step 5: Solve for x
   x = 175,499,604.92/15,123.49
6. Step 6: Final answer
   x = 11,604.44