Finding the Fourth Proportional to 2,640.72, 3,643.60 and 1,976.08

Step by Step Solution

1. Step 1: Write the proportion equation
   2,640.72 : 3,643.60 = 1,976.08 : x
2. Step 2: Convert to fraction form
   2,640.72/3,643.60 = 1,976.08/x
3. Step 3: Cross multiply
   2,640.72x = 3,643.60 × 1,976.08
4. Step 4: Simplify right side
   2,640.72x = 7,200,045.09
5. Step 5: Solve for x
   x = 7,200,045.09/2,640.72
6. Step 6: Final answer
   x = 2,726.55