Finding the Fourth Proportional to 2,101.30, 3,152.42 and 640.34

Step by Step Solution

1. Step 1: Write the proportion equation
   2,101.30 : 3,152.42 = 640.34 : x
2. Step 2: Convert to fraction form
   2,101.30/3,152.42 = 640.34/x
3. Step 3: Cross multiply
   2,101.30x = 3,152.42 × 640.34
4. Step 4: Simplify right side
   2,101.30x = 2,018,615.88
5. Step 5: Solve for x
   x = 2,018,615.88/2,101.30
6. Step 6: Final answer
   x = 960.65