Finding the Fourth Proportional to 15,661.86, 21,607.43 and 9,996.82

Step by Step Solution

1. Step 1: Write the proportion equation
   15,661.86 : 21,607.43 = 9,996.82 : x
2. Step 2: Convert to fraction form
   15,661.86/21,607.43 = 9,996.82/x
3. Step 3: Cross multiply
   15,661.86x = 21,607.43 × 9,996.82
4. Step 4: Simplify right side
   15,661.86x = 216,005,484.37
5. Step 5: Solve for x
   x = 216,005,484.37/15,661.86
6. Step 6: Final answer
   x = 13,791.82