Finding the Fourth Proportional to 21,048.72, 31,566.60 and 10,659.12

Step by Step Solution

1. Step 1: Write the proportion equation
   21,048.72 : 31,566.60 = 10,659.12 : x
2. Step 2: Convert to fraction form
   21,048.72/31,566.60 = 10,659.12/x
3. Step 3: Cross multiply
   21,048.72x = 31,566.60 × 10,659.12
4. Step 4: Simplify right side
   21,048.72x = 336,472,177.39
5. Step 5: Solve for x
   x = 336,472,177.39/21,048.72
6. Step 6: Final answer
   x = 15,985.40