Finding the Fourth Proportional to 12,456.02, 17,179.59 and 7,980.20

Step by Step Solution

1. Step 1: Write the proportion equation
   12,456.02 : 17,179.59 = 7,980.20 : x
2. Step 2: Convert to fraction form
   12,456.02/17,179.59 = 7,980.20/x
3. Step 3: Cross multiply
   12,456.02x = 17,179.59 × 7,980.20
4. Step 4: Simplify right side
   12,456.02x = 137,096,478.22
5. Step 5: Solve for x
   x = 137,096,478.22/12,456.02
6. Step 6: Final answer
   x = 11,006.44