Finding the Fourth Proportional to 12,478.49, 17,220.32 and 7,174.34

Step by Step Solution

1. Step 1: Write the proportion equation
   12,478.49 : 17,220.32 = 7,174.34 : x
2. Step 2: Convert to fraction form
   12,478.49/17,220.32 = 7,174.34/x
3. Step 3: Cross multiply
   12,478.49x = 17,220.32 × 7,174.34
4. Step 4: Simplify right side
   12,478.49x = 123,544,394.72
5. Step 5: Solve for x
   x = 123,544,394.72/12,478.49
6. Step 6: Final answer
   x = 9,900.59