Finding the Fourth Proportional to 11,665.51, 17,491.57 and 4,272.23

Step by Step Solution

1. Step 1: Write the proportion equation
   11,665.51 : 17,491.57 = 4,272.23 : x
2. Step 2: Convert to fraction form
   11,665.51/17,491.57 = 4,272.23/x
3. Step 3: Cross multiply
   11,665.51x = 17,491.57 × 4,272.23
4. Step 4: Simplify right side
   11,665.51x = 74,728,043.15
5. Step 5: Solve for x
   x = 74,728,043.15/11,665.51
6. Step 6: Final answer
   x = 6,405.90