Finding the Fourth Proportional to 1,078.50, 1,487.93 and 636.24

Step by Step Solution

1. Step 1: Write the proportion equation
   1,078.50 : 1,487.93 = 636.24 : x
2. Step 2: Convert to fraction form
   1,078.50/1,487.93 = 636.24/x
3. Step 3: Cross multiply
   1,078.50x = 1,487.93 × 636.24
4. Step 4: Simplify right side
   1,078.50x = 946,680.58
5. Step 5: Solve for x
   x = 946,680.58/1,078.50
6. Step 6: Final answer
   x = 877.78