Finding the Fourth Proportional to 1,084.65, 1,496.88 and 642.53

Step by Step Solution

1. Step 1: Write the proportion equation
   1,084.65 : 1,496.88 = 642.53 : x
2. Step 2: Convert to fraction form
   1,084.65/1,496.88 = 642.53/x
3. Step 3: Cross multiply
   1,084.65x = 1,496.88 × 642.53
4. Step 4: Simplify right side
   1,084.65x = 961,782.82
5. Step 5: Solve for x
   x = 961,782.82/1,084.65
6. Step 6: Final answer
   x = 886.72