Finding the Fourth Proportional to 1,083.50, 1,495.61 and 641.40

Step by Step Solution

1. Step 1: Write the proportion equation
   1,083.50 : 1,495.61 = 641.40 : x
2. Step 2: Convert to fraction form
   1,083.50/1,495.61 = 641.40/x
3. Step 3: Cross multiply
   1,083.50x = 1,495.61 × 641.40
4. Step 4: Simplify right side
   1,083.50x = 959,273.57
5. Step 5: Solve for x
   x = 959,273.57/1,083.50
6. Step 6: Final answer
   x = 885.35