Finding the Fourth Proportional to 1,084.45, 1,496.28 and 642.46

Step by Step Solution

1. Step 1: Write the proportion equation
   1,084.45 : 1,496.28 = 642.46 : x
2. Step 2: Convert to fraction form
   1,084.45/1,496.28 = 642.46/x
3. Step 3: Cross multiply
   1,084.45x = 1,496.28 × 642.46
4. Step 4: Simplify right side
   1,084.45x = 961,300.05
5. Step 5: Solve for x
   x = 961,300.05/1,084.45
6. Step 6: Final answer
   x = 886.44