Finding the Fourth Proportional to 11,808.72, 17,721.27 and 7,638.35

Step by Step Solution

1. Step 1: Write the proportion equation
   11,808.72 : 17,721.27 = 7,638.35 : x
2. Step 2: Convert to fraction form
   11,808.72/17,721.27 = 7,638.35/x
3. Step 3: Cross multiply
   11,808.72x = 17,721.27 × 7,638.35
4. Step 4: Simplify right side
   11,808.72x = 135,361,174.10
5. Step 5: Solve for x
   x = 135,361,174.10/11,808.72
6. Step 6: Final answer
   x = 11,462.82