Finding the Fourth Proportional to 20,196.32, 27,866.64 and 12,740

Step by Step Solution

1. Step 1: Write the proportion equation
   20,196.32 : 27,866.64 = 12,740 : x
2. Step 2: Convert to fraction form
   20,196.32/27,866.64 = 12,740/x
3. Step 3: Cross multiply
   20,196.32x = 27,866.64 × 12,740
4. Step 4: Simplify right side
   20,196.32x = 355,020,993.60
5. Step 5: Solve for x
   x = 355,020,993.60/20,196.32
6. Step 6: Final answer
   x = 17,578.50