Finding the Fourth Proportional to 11,440.72, 17,160.86 and 3,120.60

Step by Step Solution

1. Step 1: Write the proportion equation
   11,440.72 : 17,160.86 = 3,120.60 : x
2. Step 2: Convert to fraction form
   11,440.72/17,160.86 = 3,120.60/x
3. Step 3: Cross multiply
   11,440.72x = 17,160.86 × 3,120.60
4. Step 4: Simplify right side
   11,440.72x = 53,552,179.72
5. Step 5: Solve for x
   x = 53,552,179.72/11,440.72
6. Step 6: Final answer
   x = 4,680.84