Finding the Fourth Proportional to 1,103.89, 1,653.30 and 640.52

Step by Step Solution

1. Step 1: Write the proportion equation
   1,103.89 : 1,653.30 = 640.52 : x
2. Step 2: Convert to fraction form
   1,103.89/1,653.30 = 640.52/x
3. Step 3: Cross multiply
   1,103.89x = 1,653.30 × 640.52
4. Step 4: Simplify right side
   1,103.89x = 1,058,971.72
5. Step 5: Solve for x
   x = 1,058,971.72/1,103.89
6. Step 6: Final answer
   x = 959.31