Finding the Fourth Proportional to 11,709.86, 17,538.42 and 8,215.43

Step by Step Solution

1. Step 1: Write the proportion equation
   11,709.86 : 17,538.42 = 8,215.43 : x
2. Step 2: Convert to fraction form
   11,709.86/17,538.42 = 8,215.43/x
3. Step 3: Cross multiply
   11,709.86x = 17,538.42 × 8,215.43
4. Step 4: Simplify right side
   11,709.86x = 144,085,661.82
5. Step 5: Solve for x
   x = 144,085,661.82/11,709.86
6. Step 6: Final answer
   x = 12,304.64