Finding the Fourth Proportional to 2,200.08, 3,300.63 and 640.12

Step by Step Solution

1. Step 1: Write the proportion equation
   2,200.08 : 3,300.63 = 640.12 : x
2. Step 2: Convert to fraction form
   2,200.08/3,300.63 = 640.12/x
3. Step 3: Cross multiply
   2,200.08x = 3,300.63 × 640.12
4. Step 4: Simplify right side
   2,200.08x = 2,112,799.28
5. Step 5: Solve for x
   x = 2,112,799.28/2,200.08
6. Step 6: Final answer
   x = 960.33