Finding the Fourth Proportional to 12,888.72, 17,783.73 and 8,419.04

Step by Step Solution

1. Step 1: Write the proportion equation
   12,888.72 : 17,783.73 = 8,419.04 : x
2. Step 2: Convert to fraction form
   12,888.72/17,783.73 = 8,419.04/x
3. Step 3: Cross multiply
   12,888.72x = 17,783.73 × 8,419.04
4. Step 4: Simplify right side
   12,888.72x = 149,721,888.31
5. Step 5: Solve for x
   x = 149,721,888.31/12,888.72
6. Step 6: Final answer
   x = 11,616.51