Finding the Fourth Proportional to 1,920.24, 2,647.71 and 1,639.62

Step by Step Solution

1. Step 1: Write the proportion equation
   1,920.24 : 2,647.71 = 1,639.62 : x
2. Step 2: Convert to fraction form
   1,920.24/2,647.71 = 1,639.62/x
3. Step 3: Cross multiply
   1,920.24x = 2,647.71 × 1,639.62
4. Step 4: Simplify right side
   1,920.24x = 4,341,238.27
5. Step 5: Solve for x
   x = 4,341,238.27/1,920.24
6. Step 6: Final answer
   x = 2,260.78