Finding the Fourth Proportional to 2,026.50, 3,040.15 and 640.05

Step by Step Solution

1. Step 1: Write the proportion equation
   2,026.50 : 3,040.15 = 640.05 : x
2. Step 2: Convert to fraction form
   2,026.50/3,040.15 = 640.05/x
3. Step 3: Cross multiply
   2,026.50x = 3,040.15 × 640.05
4. Step 4: Simplify right side
   2,026.50x = 1,945,848.01
5. Step 5: Solve for x
   x = 1,945,848.01/2,026.50
6. Step 6: Final answer
   x = 960.20