Finding the Fourth Proportional to 1,640.01, 2,458.28 and 1,118.72

Step by Step Solution

1. Step 1: Write the proportion equation
   1,640.01 : 2,458.28 = 1,118.72 : x
2. Step 2: Convert to fraction form
   1,640.01/2,458.28 = 1,118.72/x
3. Step 3: Cross multiply
   1,640.01x = 2,458.28 × 1,118.72
4. Step 4: Simplify right side
   1,640.01x = 2,750,109.12
5. Step 5: Solve for x
   x = 2,750,109.12/1,640.01
6. Step 6: Final answer
   x = 1,676.89