Finding the Fourth Proportional to 13,036.61, 17,990.07 and 7,728.27

Step by Step Solution

1. Step 1: Write the proportion equation
   13,036.61 : 17,990.07 = 7,728.27 : x
2. Step 2: Convert to fraction form
   13,036.61/17,990.07 = 7,728.27/x
3. Step 3: Cross multiply
   13,036.61x = 17,990.07 × 7,728.27
4. Step 4: Simplify right side
   13,036.61x = 139,032,118.28
5. Step 5: Solve for x
   x = 139,032,118.28/13,036.61
6. Step 6: Final answer
   x = 10,664.75