Finding the Fourth Proportional to 13,443.18, 20,162.06 and 12,776.32

Step by Step Solution

1. Step 1: Write the proportion equation
   13,443.18 : 20,162.06 = 12,776.32 : x
2. Step 2: Convert to fraction form
   13,443.18/20,162.06 = 12,776.32/x
3. Step 3: Cross multiply
   13,443.18x = 20,162.06 × 12,776.32
4. Step 4: Simplify right side
   13,443.18x = 257,596,930.42
5. Step 5: Solve for x
   x = 257,596,930.42/13,443.18
6. Step 6: Final answer
   x = 19,161.90