Finding the Fourth Proportional to 12,886.20, 17,791.52 and 9,896.69

Step by Step Solution

1. Step 1: Write the proportion equation
   12,886.20 : 17,791.52 = 9,896.69 : x
2. Step 2: Convert to fraction form
   12,886.20/17,791.52 = 9,896.69/x
3. Step 3: Cross multiply
   12,886.20x = 17,791.52 × 9,896.69
4. Step 4: Simplify right side
   12,886.20x = 176,077,019.63
5. Step 5: Solve for x
   x = 176,077,019.63/12,886.20
6. Step 6: Final answer
   x = 13,664.00