Finding the Fourth Proportional to 12,936.72, 17,852.20 and 7,909.36

Step by Step Solution

1. Step 1: Write the proportion equation
   12,936.72 : 17,852.20 = 7,909.36 : x
2. Step 2: Convert to fraction form
   12,936.72/17,852.20 = 7,909.36/x
3. Step 3: Cross multiply
   12,936.72x = 17,852.20 × 7,909.36
4. Step 4: Simplify right side
   12,936.72x = 141,199,476.59
5. Step 5: Solve for x
   x = 141,199,476.59/12,936.72
6. Step 6: Final answer
   x = 10,914.63