Finding the Fourth Proportional to 2,101.49, 3,152.12 and 640.52

Step by Step Solution

1. Step 1: Write the proportion equation
   2,101.49 : 3,152.12 = 640.52 : x
2. Step 2: Convert to fraction form
   2,101.49/3,152.12 = 640.52/x
3. Step 3: Cross multiply
   2,101.49x = 3,152.12 × 640.52
4. Step 4: Simplify right side
   2,101.49x = 2,018,995.90
5. Step 5: Solve for x
   x = 2,018,995.90/2,101.49
6. Step 6: Final answer
   x = 960.74