Finding the Fourth Proportional to 20,858.48, 28,785 and 12,473.36

Step by Step Solution

1. Step 1: Write the proportion equation
   20,858.48 : 28,785 = 12,473.36 : x
2. Step 2: Convert to fraction form
   20,858.48/28,785 = 12,473.36/x
3. Step 3: Cross multiply
   20,858.48x = 28,785 × 12,473.36
4. Step 4: Simplify right side
   20,858.48x = 359,045,667.60
5. Step 5: Solve for x
   x = 359,045,667.60/20,858.48
6. Step 6: Final answer
   x = 17,213.41