Finding the Fourth Proportional to 2,200.16, 3,300.46 and 640.18

Step by Step Solution

1. Step 1: Write the proportion equation
   2,200.16 : 3,300.46 = 640.18 : x
2. Step 2: Convert to fraction form
   2,200.16/3,300.46 = 640.18/x
3. Step 3: Cross multiply
   2,200.16x = 3,300.46 × 640.18
4. Step 4: Simplify right side
   2,200.16x = 2,112,888.48
5. Step 5: Solve for x
   x = 2,112,888.48/2,200.16
6. Step 6: Final answer
   x = 960.33