Finding the Fourth Proportional to 21,144.26, 31,720.04 and 7,105.64

Step by Step Solution

1. Step 1: Write the proportion equation
   21,144.26 : 31,720.04 = 7,105.64 : x
2. Step 2: Convert to fraction form
   21,144.26/31,720.04 = 7,105.64/x
3. Step 3: Cross multiply
   21,144.26x = 31,720.04 × 7,105.64
4. Step 4: Simplify right side
   21,144.26x = 225,391,185.03
5. Step 5: Solve for x
   x = 225,391,185.03/21,144.26
6. Step 6: Final answer
   x = 10,659.69