Finding the Fourth Proportional to 2,200.22, 3,300.82 and 640.30

Step by Step Solution

1. Step 1: Write the proportion equation
   2,200.22 : 3,300.82 = 640.30 : x
2. Step 2: Convert to fraction form
   2,200.22/3,300.82 = 640.30/x
3. Step 3: Cross multiply
   2,200.22x = 3,300.82 × 640.30
4. Step 4: Simplify right side
   2,200.22x = 2,113,515.05
5. Step 5: Solve for x
   x = 2,113,515.05/2,200.22
6. Step 6: Final answer
   x = 960.59