Finding the Fourth Proportional to 1,083.78, 1,495.67 and 641.52

Step by Step Solution

1. Step 1: Write the proportion equation
   1,083.78 : 1,495.67 = 641.52 : x
2. Step 2: Convert to fraction form
   1,083.78/1,495.67 = 641.52/x
3. Step 3: Cross multiply
   1,083.78x = 1,495.67 × 641.52
4. Step 4: Simplify right side
   1,083.78x = 959,499.01
5. Step 5: Solve for x
   x = 959,499.01/1,083.78
6. Step 6: Final answer
   x = 885.33