Finding the Fourth Proportional to 11,601.72, 17,371.68 and 7,911.20

Step by Step Solution

1. Step 1: Write the proportion equation
   11,601.72 : 17,371.68 = 7,911.20 : x
2. Step 2: Convert to fraction form
   11,601.72/17,371.68 = 7,911.20/x
3. Step 3: Cross multiply
   11,601.72x = 17,371.68 × 7,911.20
4. Step 4: Simplify right side
   11,601.72x = 137,430,834.82
5. Step 5: Solve for x
   x = 137,430,834.82/11,601.72
6. Step 6: Final answer
   x = 11,845.73