Finding the Fourth Proportional to 13,978.40, 19,290.48 and 8,009.36

Step by Step Solution

1. Step 1: Write the proportion equation
   13,978.40 : 19,290.48 = 8,009.36 : x
2. Step 2: Convert to fraction form
   13,978.40/19,290.48 = 8,009.36/x
3. Step 3: Cross multiply
   13,978.40x = 19,290.48 × 8,009.36
4. Step 4: Simplify right side
   13,978.40x = 154,504,398.89
5. Step 5: Solve for x
   x = 154,504,398.89/13,978.40
6. Step 6: Final answer
   x = 11,053.08