Finding the Fourth Proportional to 1,103.93, 1,653.72 and 640.73

Step by Step Solution

1. Step 1: Write the proportion equation
   1,103.93 : 1,653.72 = 640.73 : x
2. Step 2: Convert to fraction form
   1,103.93/1,653.72 = 640.73/x
3. Step 3: Cross multiply
   1,103.93x = 1,653.72 × 640.73
4. Step 4: Simplify right side
   1,103.93x = 1,059,588.02
5. Step 5: Solve for x
   x = 1,059,588.02/1,103.93
6. Step 6: Final answer
   x = 959.83